I've got cage pedals on my bike but they were missing the clips when I bought the bike, so essentially just platforms. This works for me, since I use the one bike for everything-utility, commuting, sport/exercise and riding to the bars at night. Nice and simple.

I've been considering powergrips though-- seems like a solid blend of foot retention/power and versatility/ease of use. Clips seem like a hassle for the short rides I do, and clipless are just too expensive (and you can't wear flip flops!)