Sebastian,
That's hard to say, really. It depends on your development environments I guess. I use eclipse/FDT for flash development so all my paths to my code bank and stuff like that is saved in one preferences file which I can then load up on any machine. of course the problem with that is that the code bank has to sit in exactly the same spot on the new computer which isn't always the case, but luckily i develop on my laptop and have that with me when i go elsewhere so i don't have this issue. i guess for what you are doing that's the best way, its just a hassle to have to do it like that when you develop on one machine.
alternatively, you could set up an SVN repository on google code for instance and connect to it from whatever computer you are on and grab the latest versions of your code bank, but i'm not sure how familiar you are with SVN or how comfortable you would be doing that so it may not be a solution you could tackle.