Shasplit takes a large data block, splits it into smaller parts, and puts those parts into an SHA-based content-addressed store. Reassembling those parts is a trivial "cat" invocation. Repeating parts (e.g., from previous split operations) are stored only once, which allows efficient incremental backups of whole LVM snapshots via Rsync. Shasplit shows its strengths on encrypted block devices, but might be useful for non-encrypted data, too.
The TI-BASIC Compiler allows you to write TI-BASIC programs for the Texas Instruments TI-83 and TI-84+ calculators using your computer instead of the calculator's keyboard. This allows you to spend more time writing code than navigating menus or trying to scroll around the tiny screen on the calculator.
clens is a convenience library that aids in porting code from OpenBSD to different operating systems. Operating systems traditionally have different enough APIs that porting code is painful and can litter pretty code with ugly #ifdefs. In order to keep code readable and drastically reduce the number of #ifdefs needed, clens brings other APIs or missing functions into specific OS "focus".