I have been looking at the source code of Hubski pages recently and it occurred me that there perhaps could be an easy way to limit bandwidth use. While it's only a tiny bit, enough drops make a puddle.
What I have noticed is the fact that the 'tutorial' gets to be downloaded each time, despite being rather unlikely to be used aside of fresh users more then once or twice. Would it be possible/worthwhile to make it redirect to a page with an overlay for tutorial and thus removing it from every other generated page? This idea occurred to lm and me when we were talking on IRC about the service.
Just food for thought.
EDIT: To put an intuitive number on it, removing it saves ~3KB per page refresh. According to sites like this one or this it would mean around a bit over 14MB saved per day, that translates to about 430MB per month. More for the second estimation. This could be presumptuous of me but depending on your hosting this could actually save bandwidth expenses. Sorry for back-of-the-envelope calculation on imprecise data, but I do have a gut feeling that it could indeed benefit (or rather 'cost you less' to avoid marketer speak) you in the long run.