UPX: the Ultimate Packer for eXecutables [How to save space on your Thumb/Pen/USB Drive]

UPX: the Ultimate Packer for eXecutables - Homepage

"UPX is a free, portable, extendable, high-performance executable packer for several different executable formats. It achieves an excellent compression ratio and offers very fast decompression. Your executables suffer no memory overhead or other drawbacks because of in-place decompression ..."

As a follow-up to my Directory of Programs for USB Drives post I came across the UPX utility (via a comment on the original post referring to What's on my Pen Drive?).

UPX sounds pretty interesting. I still have 100MB free on my thumb/pen/USB drive, but I can see it filling quickly... 40'ish percent saved space... Yes, interesting.

For real world space saving results with UPX, see What's on my Pen Drive? (scroll down toward the bottom).