hungrycat is a tool that prints contents of a file on the standard output, while simultaneously freeing disk space occupied by the file. It can be useful if you need to process a large file, but you don't have enough space to store the output file and you wouldn't need the input file afterwards.
License: The Expat license
Version: 0.3.1 released on 2013-06-12
$ md5sum bigfile
d9b18676a36c919c1688cba61a2cf0f1 bigfile
$ ls -lh bigfile
-rw------- 1 jwilk users 281M Sep 13 19:46 bigfile
$ df -h .
Filesystem Size Used Avail Use% Mounted on
/dev/ice9 330M 284M 29M 91% /mnt/ice9
$ hungrycat bigfile | bzip2 > bigfile.bz2
$ ls -lh bigfile*
-rw------- 1 jwilk users 60M Sep 13 19:49 bigfile.bz2
$ df -h .
Filesystem Size Used Avail Use% Mounted on
/dev/ice9 330M 63M 251M 20% /mnt/ice9
$ bzcat bigfile.bz2 | md5sum
d9b18676a36c919c1688cba61a2cf0f1 -