Many thanks to all who responded with advice to caspoobear's question. I received a ton of used college t-shirts for Christmas (not what I asked for, but you know how that goes), so I'll be making a t-shirt quilt in the future. I, too, wondered about the sashing. . . Now I know!

Just realized I am missing at least 6 years' shirts before I can figure out the size it is going to end up. Do people generally cut the shirts all the same size (the size of the biggest print) or cut whatever size each print is?
Thanks for all your tips!

here is one of the ones I did....

http://www.quiltingboard.com/t-11084-1.htm

as you can see for mine it was random sizes. If you type in the search box ..t-shirt quilts.. you can see others. Mine looks like a postage stamp, I am getting ready to make another one like this one.

Ditto Here!

I've done it a few ways. I stabalized the shirts and then framed them in flannel -- then make a rag quilt out of the squares.

sashed with cornerstones, without cornerstones, made a funky shape out of the shirts, made with homemade charm packs, made with super thin strips, made by framing and sashing. the key is to have fun, and to make sure the shirts are all facing the same way!!

In the interest of having a life, I decided against sashing but am going to just do a border. I have the shirts all together, have to get the borders together and then on. Then layer and tie. Hopefully this weekend still, sometime between working both days, church and a massage. Maybe I will just hope to get the borders together and on and do the rest later, I still have some time.