Depending on your style, there is a lot of flavors of clerics one can choose from. Some I've seen and/or played:
1. Uber-healer: Go for the Radiant Servant of Pelor. Also makes for a decent anti-undead type.
2. Necromancer: This is my personal favorite style of cleric. It is a bit weak on healing, but the ability to command undead can be extremely useful (skeleton, I command thee to go disarm that trap.... BOOOM!). Go straight cleric or aim for the True Necromancer. Lots of good stuff in Libris Mortis here.
3. Controller: A friend of mine did this - he went with I think Domination and one of the elemental domains. Also works well with 2 elemental domains. Take extra turning and just control, command, and turn things. Can also consider channeling negative energy so you can command undead too.
4. Divine Feats (this one might not work too well as you're after a caster). A trick I've seen used is to take a single cleric level to get the turning, then use the turn attempts to power divine feats. This can be very effective depending on what its combined with.
You didn't indicate what level you're planning on playing and which world. That can make a bit of difference sometimes for planning.