Check out this article on 39 ways to repurpose your old t-shirts.
The subtitle says, "Finally a use for all those shirts you've been sentimentally hoarding over the years." Guilty as charged!
Some of it looks like a lot of work, but what a fun project to take on! I like the tote bag and the knot headband.
39 Ways To Reuse, Restyle, And Rewear Your Old T-Shirts