Lately I'm not on really good terms with my once shiny gadgets, but I can't pinpoint the problems, really. Well, maybe I have a good guess, but then I'd written this wall of text for naught.
Hardware
Let's start with a list of my current "mobile" hardware.
Lenovo ThinkPad W500
Work laptop, bought in Summer 2010. In general I'm very fond of it. It gets the job done, although it's only a Core2Duo with 8GB of RAM - nothing fancy like i3 or i5. I can run 2 VMs and still do what I need to do. It's usually hooked up to a 24" Dell screen, so I run 2x 1920x1050/1200. There's one huge downside: the battery power is just abysmal. Without high load, it's still dead after less than 3h. There's also my main point of criticism with Debian - there's no "put down lid to sleep" - the feature I envy most of MacBook users. (No, I haven't played around it with it for hours trying to fix it, I have an SSD and can usually hard-suspend and wake without a problem.) Then I'm too lazy to fiddle with putting on full-disk encryption, and I don't remember why I didn't use it when installing in the first time, 2.5 years ago. The backlight is dying slowly, maybe I need this to be replaced soonish. No problem working in a dark room, but in daylight it sucks a little already.
Fujitsu S710
It's not a bad laptop, it has an i5 and 2 GB of memory (don't ask, not my choice), but the battery is even worse. I think I can get 2.5h of any non-compiling work out of it before it shuts down silently without a warning beep. (Again, too lazy to dig into this issue, that's some stuff where I don't want to spend hours of my life.) The fan randomly spins up (just like with most colleagues' MacBook Pros in the office) without any load on it. It also runs Debian testing, and mighty fine I might add.
HP nx7010
Ah yes, my first laptop, bought in 2004 - 1.6 GHz Centrino single core, upgraded to 1.5 GB of RAM. Right now it runs ArchLinux but the last update broke X and I really didn't need it so far so this is still unfixed. If watching HTML5 and/or Flash movies wouldn't bring it to it's knees it might still my number one couch surfing device, as it handled all tasks I threw at it so far, albeit slowly. Pain point (and I guess I'm repeating myself) is the battery. It lasts between 2h and 3h - for once what you do actually matters, but still, this is terrible.
Asus eeePC 900A
It's just over 4 years old and the display stopped working recently, but I'll have to hook it up to an external screen to declare it totally dead. For the price it was actually awesome and I've taken it on more trips to more countries than most of the other devices combined. The keyboard wasn't totally easy to type on, the screen was small and the SSD was kind of slow but it run for over 3h and I could easily pack it to any location. It actually really saved my ass once when the power adapter of my HP laptop died while on vacation in Italy. I (very quickly) copied over a few documents and could continue writing my diploma thesis.
ainol Novo 7 Tornado
My 7" Android tablet I bought in Hong Kong for 65 EUR. Perfect device for those times where all computers are shut down (like just after getting up) to check public transport schedules, play a few games when bored for 15 minutes or light browsing. I just can't get anything closely relatad to work done. The display isn't as brilliant as the Nexus 7 which I originally planned to buy until I found this thing by chance and the touch screen can be a little fiddly - for the amount of use it gets I'm much happier to have saved 135 EUR.
HTC Desire Z
My mobile phone of choice. My first Android was a HTC Click/Tattoo which was cheap at the time and the perfect thing to get me hooked on Android. But the display wasn't exactly brilliant and it was very slow with the stock ROM and still slow with CyanogenMod. The Desire Z has a hardware keyboard and I'm generally very happy with it. That it only lasts for one day doesn't usually annoy me, but if I have to use it for the whole day (because all my other devices are powerless) it's just not enough. I know, I could buy a better battery. The hardware keyboard is fine for using IRC or the eventual emergency SSH login - it's not a full replacement. My number one use case is probably reading feeds on the subway.
Kindle
It's not yet arrived, but I'm looking forward to reading a few more books on the subway. Got it while it was on sale for 59 EUR yesterday, finally a "no more thinking, just try it out" moment.
Interlude
So, yes, I think it boils down to me being pissed a bit about not being able to comfortably use a laptop on conferences if there's no power outlet near. Many people I know have their main machine with them most of the time, this is clearly not for me - I can tell that much. But even juggling mobile devices, on every small or big trip trying to find the right thing... Maybe it's time to move on and buy a "new" machine instead of relying on unwieldy 9, 4 or 3 old ones, if only it wasn't for the steep price of decent ones. Then again my personal laptop usage is far from exhaustive - let's say once or twice per week for a few hours and then a few conferences or other trips per year.
Software
Not a big point, really. I've been using Debian testing for years and the longest I took to fix something seriously broken was about 30min (by debugging and then replacing gdm with xdm). Dual boot would be nice but is in no way obligatory and Windows would probably be booted as much as now - once a month for a movie. (Again I couldn't be assed to make it work on Linux when it already has Windows on it and I'm booting anyway. It seems I've really gotten lazy over the years. I won't fix broken things if I don't need to.)
Obstacles
Unlike other people I'm not actually looking forward to new stuff. Installing, configuring, meh. I'm not really needing it either, the current setup works well enough to not get angry enough to replace something. And, mostly, I'm to cheap to buy a laptop for 1000 EUR if I have a somewhat working setup.
Solutions
From what I've seen the Lenovo x230 seems kind of perfect for my use case. It's big enough to get work done, I tried the keyboard and actually liked the new clicky keys and it seems to run forever. The downside is the price and I'm also not sure the screen is big enough to be able to work on it for 8h a day. Speaking of battery life I'd probably even be happy with a MacBook Air, especially while travelling. I'm still no fan of OS X, but when I'm not at home or in the office being able to use the computer trumps being totally happy with all the small details. Of course there should be a few more light 13" laptops out nowadays, but so far I've been absolutely happy with the 2 Lenovos I used and I don't really want to buy a Mac, especially when the only reasons are battery life and some minor conveniences regarding WLAN usage (from what I observed). Maybe I should just buy a few additional batteries and be done with it.