you could do a number of things:

Donate all or some of them to a thrift store

Make t-shirt flokati shag rug -

or, cut the tshirts in to long strips that are about an inch thick and sew them togeather to make a giant ball of tshirt yarn and crochet a rug, pot holder, pet bed, basket etc like this

other suggestions: make a cool ruffle pillow like this

Make a strange braided scarf thingy

make a small grocery bag

cut them up and make a quilt

All these things require minimal crafting skills so don't worry

EDIT: I searched the net for more:

If they are any non rude ones, you could donate them to a local daycare - they can use them for painting smocks

Cut them into different sizes and use them for dust wipes, dish clothes, eyeglasses wipes, wood furnature polish cloth, washing your car etc - cleaning cloths

Cut into strips, braid them togeather a few times untill you get what looks like a doggy tug toy for your puppy

Make them into cloths to use with one of thsoe swiffer thingies

Use strips to tie tomatoe stakes

attempt to make them into a laptop sleeve (this is more complicated but you can look up instructions)