i got this idea from chez larsson (http://chezlarsson.com/myblog/2009/06/from-tshirt-to-pillow-.html). benita made a pillow for her son's room from an i <3 ny shirt that (i think) was too small.
i got this low t-shirt at a show approximately five years ago - and two kids ago. i wasn't thin pre-kid, but like many of my old shirts, it's somehow way too short now. i was hanging on to it for something (i think i was planning to remake it into a kid shirt?) but this idea is perfect for it. no one will ever grow out of it again!
bonus: i got the pillow form (new in package) at the thrift store for 49 cents.