I typically go the lazy route and do like @uncdeo and just push more beer through my lines. After my knee surgery and going a few weeks without beers ready to go, I decided to break down and actually clean my lines and faucets.
I used liquid beer line cleaner and used my little pump from my carboy washer to recirculate it through based on a post I'd seen on here a while back. Then I recirculated plain water for a few minutes to rinse and finally used Star San pushed up from a clean keg, which both served to hopefully completely purge the keg to be ready for next use and sanitized my lines. It maaaaaay have been two years since I last did that.