The tools I use for computer forensics.

Windows

• Recuva – Excellent at recovering data from Windows partitions and free to boot.
• UFS Explorer – Not free, but is able to recover from linux partitions (Recuva is better for FAT/NTFS)
• explore2fs – Access linux partitions from Windows. Free.
• HFSExplorer – Access Mac partitions from Windows

Linux

• Hiren’s Boot CD – Contains an impressive lineup of programs for computer forensics, but its legal status is often debated.
• Trinity Rescue Kit – A live distro with backup programs, Midnight Commander, testdisk, shell and other good stuff. Legal!