On a recent quest for information on help desk software, I came across a free package that almost rivalled the industry leading eSupport from Kayako. If you’re looking for an online help desk and knowledge base package then do consider Cerberus. You’re limited to managing a single email address for queries, but commercial use is permitted in the free licence. Powerful, highly configurable, customisable and well-supported. Typically used by web hosts, Cerberus is definitely worth a look before you dig into your pockets.