Mihai Criveti has published a list for digital forensics work. This page is worth bookmark:
Computer Forensics is a science and an art. And to perform it, you need tools to identify, acquisition, preserve and analyze data in a clean, safe, non-destructive manner. Lots of tools. Everything from data acquisition to virtualization and steganalysis.
A list of more or less free tools (mostly open source or freeware, but I have included some relevant commercial products) no digital forensics expert should be without