Do you want free gear? Then wear testing might be the thing for you. Minimal work is required and if you are like me and like to think that your opinion is going to influence a future product, then that is just an added bonus.
How do you become a wear tester? Go onto one of the shoe company's websites and apply.
New Balance Wear Test
Brooks Wear Test
Mizuno Wear Test
Nike has one too that is somewhat hard to find and also harder to get into. I have wear tested for New Balance a few times and have friends who have tested for Brooks and Nike.
If you like to run, like to try new things, like free stuff (may or may not get to keep it), and like to help develop a product then wear testing is for you.