My wife poses this question quite often.
I have in my possession way too many of these shirts. In fact, my drawers often overflow with them. However, I enjoy keeping memories of the various race events in which I participate.
There's only so much room. Every so often I have to go through them and clean up. Blogger Christine Luff has some some ideas on what to do with these shirts when you get through your drawers and clean them up. Donate them, use them as rags and more.
Next time you clean up those shirts, here are some good suggestions as to what you can do with them.