I don't think $30-50 is too much. Remember, these guys are paying for their tuxes, and giving up a perfectly good weekend (especially if they are traveling) to help you out. Be good to your ushers and groomsmen. Perhaps we have a different definition of usher, but all of my ushers stood up with me at the front. The one person who you may want to do something extra special for is your best man.
Personalized gifts are the best option. I wish I had spent more time on the gifts I gave my groomsmen. I didn't even think to personalize it because I thought it was tradition to get them all the same thing. Things like flask are appreciated by the college age crowd, but once he is old enough to know better, it becomes a dust collector somewhere. Memories are probably the best thing - the guy who posted about the a skins jersey and Patriots (GO PATS!) movies was right on. Those are great gifts that will always be appreciated. I would avoid events like paying for a trip to the barber - you should do that anyways.
