When I kick a keg, I rinse it out very well, and give it a short soak with oxyclean and hot water, shaking occasionally. I remove the posts just long enough to spritz some hot water down the pickup tubes and rinse the posts off in HOT water.
Once the keg's rinsed and reassembled, I fill it with 1/2 gallon of sanitizer (I generally use iodophor), and store under a bit of pressure to keep the keg sealed up. I rebuild a keg every 3 or 4 uses, which works out to once a year or so with six kegs in the rotation. I clean my beer lines, couplers, and taps (I still use picnic taps, but with 10' lines) with hot water and sanitizer when I clean the keg, or whenever I need them to transfer wort/finished beer into the keg.
When I'm ready to fill the keg, I use the residual pressure in the keg to discharge the sanitizer, and I'm good to go.