TRUE Online Collaboration (a myth turned true??)

I was reading some stuff on how people can produce music together at a distance...

I found Dropbox which is more or less "content"-independent but the files are sync'ed and updated if one of the members does something new... this could prove interesting as long as we're using the same tools..(It's actually a SVN for dummies - like most of us probably)

The other one is RiffWorks-T4 which could be quite interesting... I'm still to spend a couple of hours to know the "if's" and "do's" and "don'ts" of it but.... I'd like to think that decisions should be taken with maximum of possibilities at hand!!!

Hope to get some feedback soon!!