It is an intriguing thought: what happens if a paladin, of all people, loses faith in his chosen deity? This paragon path suggests how such a dramatic turn of events can be used to advantage - and may even encourage the more adventurous role-player to make such a move.
In keeping with One Bad Egg's stated ideals of just giving you ideas to get your own creative juices flowing, the reasons why a paladin might turn away from his god are left open - it could be something the god has done (if your deities are interventionist this is quite possible!) or growing cynicism about the whole religion thing might have led him to believe that his power comes from within rather than above. Be that as it may, once the paladin character has lost his faith, this work suggests a way in which he can continue as a paladin, but with different powers stemming from within (or perhaps from his deity who may not have abandoned him!). Various path features and prayers are given, along with a useful magic item and an excellent feat that is of general application.
This feat, Personal Code, is worthy of special mention. It can be taken by anyone who wants to have a firm moral code by which to live, a code which may be derived from the tenets of a religion or from a particular ethical stance either derived by the character himself or taught by a secular group or teacher. The fun thing is, it should be written in such a way that it provides in-game challenges to the character and these, provided the DM agrees, can be used to create milestones and minor quests with the concomitant rewards.
You also get a couple of monster templates, not only player-characters desert their gods after all! So there's a template for humanoids and another for fallen angels. Very useful for any campaign in which individual relationships with the gods are important.
Worth it for the Personal Code feat alone, this is an intriguing concept well-presented.