THQ has announced that a Titan Quest expansion pack will be released before the end of Q1, but there are other options for extending your mythical adventures beyond the game's core campaign. Aspiring developers have started showcasing their mods at the Titan Quest Vault, and have offered some insight into their creative process through a series of interviews.
German modder Toh Klidan, for example, is the author of Andromeda's Sacrifice, a retelling of the classic tale of the Aethiopian princess and her savior Perseus (of Clash of the Titans fame). According to Klidan, the Titan Quest tools appear more confusing than they actually are, so we should be seeing more independent campaigns and maps in the near future. There are over 40 available now. Let us know if you've tried any of them.
See also: Metareview - Titan Quest