- 7-Zip [GNU LGPL]
- Zzip [GNU GPL]
- Info-ZIP
- GreenEye (can anybody provide me the official GreenEye link?)
- BiGZiP [GNU GPL or LGPL]
- Open-source ARJ [GNU GPL]
- Ultimate Packer for eXecutables (UPX) [GNU GPL]
Misspellings: xompression, vompression, fompression, dompression, cimpression, ckmpression, clmpression, cpmpression, c0mpression, c9mpression, conpression, cokpression, cojpression, comoression, comlression, com-ression, com0ression, compeession, compdession, compfession, comptession, comp5ession, comp4ession, comprwssion, comprsssion, comprdssion, comprrssion, compr4ssion, compr3ssion, compreasion, comprezsion, comprexsion, compredsion, compreesion, comprewsion, compresaion, compreszion, compresxion, compresdion, compreseion, compreswion, compressuon, compressjon, compresskon, compressoon, compress9on, compress8on, compressiin, compressikn, compressiln, compressipn, compressi0n, compressi9n, compressiob, compressiom, compressioj, compressioh, ompression, cmpression, copression, comression, compession, comprssion, compresion, compresion, compresson, compressin, compressio, ocmpression, cmopression, copmression, comrpession, comperssion, comprsesion, compression, compresison, compressoin, compressino, ccompression, coompression, commpression, comppression, comprression, compreession, compresssion, compresssion, compressiion, compressioon, compressionn, xip, sip, aip, zup, zjp, zkp, zop, z9p, z8p, zio, zil, zi-, zi0, ip, zp, zi, izp, zpi, zzip, ziip, zipp