I tweeted the other day (follow me @meredithjgordon) that besides my shoes, the piece of running equipment I use most often is my reflective vest. Seriously, I probably use it 3-4 times per week. It was probably the best $20 I've spent on running equipment. (You can read about the best money I ever spent on triathlon here.)
So this begs the question, what's the item you use the most, love the most, best money you've spent on running or triathlon equipment? Leave me a message!