Disk Drill 2.4

Disk Drill is available in a Free/Basic version and a Pro version for $89.
Disk Drill is a Mac data recovery software designed natively for Mac OS: easily protect your files from accidental deletion with Recovery Vault and recover lost data from Mac disks.

When something is deleted Recovery Vault makes it possible to recover not only the file itself, but also its properties, such as original file name, location, etc. So you will always be able to recover data from Mac files system (HFS/HFS+) and FAT32 partitions. Disk Drill also includes powerful S.M.A.R.T. disk monitoring right out-of-the-box; you can monitor your disks' hardware status and get automatic notifications of potential failures or other issues. If a disk or partition is failing, you can easily backup it into a disk image (DMG) which can later be mounted for recovery.
Disk Drill PRO also features a number of advanced scanning modes for data recovery of FAT, NTFS, HFS/HFS+, other file systems and formatted (initialized) drives. Using Quick Scan you can locate deleted items on FAT and NTFS disks, this scanning method is fast and accurate, but is unlikely to find data deleted long ago. With Deep Scan you can try to recover data from any disk or memory card regardless of their file system. This recovery method is long and thorough, it scans your disk in a binary mode and is capable of finding deleted files even after formatting.