I still find .tar.gz (Tarred and GZipped) to be the best universal format.

If you look at Sourceforge or similar places the files are always smaller than standard Zip - not as small as 7-Zip though. It's also guaranteed to work on just about every machine known to man without extra software (OK, on Billyware you need to use a 3rd party program - but that's par for the course).

7-Zip is good, but it's not a universal format - I'm talking BSD, AIX, Solaris etc etc here.

Bob