I admit that I hoard too many things. It's mainly laziness: I replace my skate laces and when DH cleans up after me, he just tosses them in the shoe care box with the polish, brushes and Snowseal.
Both my dds are doing marching band this year. Their band requires something called a "dot book," which I've learned is a small spiral notebook strung on a shoelace. They can wear them around their necks like lanyards or around their waist like a belt. (From what I've seen on the web, it would probably be good for synchro teams!
http://en.wikipedia.org/wiki/Dot_book )
Voila! A use for those old skate laces! We bought new books for the new season and I gave each one a used skate lace to use. Told 'em that, if the lace is too long, cut it and share with someone else or toss the extra piece!