Those big Marvel/DC titles are ok, but give the less main stream stuff a chance too. Generally, I find the titles I've listed to be better written, more hardcore, original, and entertaining. You reach a point where reading about [random hero/super team] saving the [city/earth/universe/all reality] from [random villain/evil force] just doesn't do it anymore =). Try these
1 - Preacher by Garth Ennis
2 - Watchmen by Alan Moore
3 - Fables by Bill Willingham (ongoing)
4 - Top 10 by Alan Moore
5 - Bone by Jeff Smith
6 - Astro City by Kurt Busiek
7 - Boneyard by Richard Moore (ongoing)
Go read Preacher and then we can discuss it in my Preacher thread =).