Recently I've begun programming this year for a course I am taking [nothing fancy; c#]. Realizing that sometimes I'd like to do programming elsewhere, that would mean I'd need a laptop. I'd want to get a fullsized laptop [no netbooks] but at the same time not be too expensive [$300-400 max]. Any recommendations, or can I really just choose any old laptop, install a Linux distro on it [looking at Arch Linux], just do programming on it? Also, was considering making it the primary OS as well, so are there any people who use Linux as their primary OS on either a laptop or desktop?