I have two (supposedly) identical laptops. I mainly use one, but always keep a backup on the other so the most I'll ever loose is a days work.
There are a lot of things to talk about regarding the problems of keeping two identical laptops. I've decided its time to upgrade from XP to Windows 7. So I spent the day a few days ago installing Windows 7 over my Vista machine (it was originally Vista but I hated it so much I rolled back to XP). It installed nicely right on top without any special changes.
So far I've had no complaints and its been able to run all my software including some of the rarer translation and dictionary stuff. All my free software like Avira, VLC, firefox installed with absolutly no problems too.
So over all I'm rather happy with Windows 7. I'll keep one laptop on XP and the other in Windows 7 for a while and if it still goes well in a couple of months I'll try to upgrade the other one too.
This leads me to my main gripe! In order to do this I will have to buy two separate copies of Windows 7. I don't think keeping two laptops is particularly unusual and i don't think I should be made to pay 130GBP for another copy. What bugs me is that Microsoft continually do little things like that to make a bit of extra profit here and there, and they then complain about software piracy.
I'm not supporting piracy, but in cases like mine I've actually got quite a lot of sympathy for people who feel hard done by.
However, Windows 7 has so far run very well! A huge improvement on Vista, and almost as good as XP!