One problem I've been encountering a fair amount this month is forgetting my keys. Since hooking my keys to my belt loop with a carabiner isn't quite cutting it, I've decided i need to make myself a wrist cuff to tuck my room key inside of. I stumbled upon this tutorial for one (literally, stumbleupon.com) and think I'll take the basic idea from it, though its a pretty simple idea. I'll probably replace the velcro with buttons. And maybe just a flap instead of a zipper.
I'll post pictures of the process and final product when I'm done. :)