I keep 'em... (unless they're rank!) they go in the "souvaneer" box with noteable posters, pics of fans and titties seen at shows and reviews and such...
Free stuff? Gah... If I had a DIME for every piece of bar/pub/festival swag I've collected, I wouldn't need to play places that HAVE to give stuff away for free to get people to come in...
A few metric TONS of various T-shirts... beer companies... pubs... festivals... key chains... gaaaaah! I've got a BOX of various and sundry key-chains... some are even mini-flashlights.... Temp tatoos! By the box full! Stickers in nearly every shape and form! Rolls of stickers... That makes great 'wallets' (like the duct tape wallets found online) Bar Towels... 9 or 10 at least... waitress aprons... 3 or 4... I have SO much plastic Guinness 'banner' that I used it to cover a WALL in my basement when I built my speak-easy... and I gave one roll of it away... and I STILL have WAY too much of it left... I got a Glenfiddich promo calculator... it looks like a little 'box' that you'd get a bottle in, but a paper thin, solar calculator rolls out of one side of it... hats... if it's a 'ball cap' I leave it behind at the gig, no matter who gave it to me... if it's a 'cap' then sure... I'll keep it... (I actually need to get a new Guinness cap... mines been worn so much that NO ammout of Febreeze is gonna take the head-sweat stank outa it! Use my Tartan Special 'fanny pack' as a camera and mini-disc player bag... gym bags... Kieths... and ummm... some cruddy whiskey... the Kieths one was garbage, but the whiskey one we still use...
I'm sure there's plenty more...
Oh ya... a Guinness bar 'light'... that's one I kinda relish having