Retrocomputing is a bit of a minor hobby of mine, and I presume its a popular hobby for lotsa' hackers. We just all seem to collect old parts around us, don't we?
Retrocomputing many times is a descent into nostalgia; a chance to visit a time when things were different, in the same way that people fix up antique cars or restore old Victrolas. It is also a chance to get the top of the line machine we always wanted but never had -- technology of the now is moving too rapidly to have anything really solid. Retrocomputing is a chance to freeze time almost and have a chance to do more then you usually would have the wherewithall to do.