I live in a rural area, and have had rodent issues.
The home-made bucket o water trap is the best trap I have seen. The snap traps work well, if you make sure the bait is very securely connected. Glue traps work very well. Also a hungry, half wild, homeless cat is effective, but it can't be a well feed, good looking cat from the pet store, it has to be an angry beast that grew up on its own without human love, and now kills for the fun of it. Female cats of this variety are better than male cats, the male cats will eventually wander off in search of female cats. Shooting them with a pellet gun is fun, but if you are not staying up all night constantly popping them you are not as effective as a trap. Poison has not been very effective from my experience.
Edited to add (Although if you are going to leave pizza crusts laying around you are always going to have rodent issues. I hate to blame the victim here, but I mean, left over pizza will always attract rodents and teenage boys no matter what you do).