I voted for zip.
Why? Because it's standard (I know abandonia is breaking every standard :bleh: )
I have 56k connection, but I don't mind.
If you haven't noticed WinRar has compression metods which vary from fastest (larger) to best (smaller file size).
So if you didn't use WinRar's best compression metod - GET TO WORK!!!
Just to mention this can be used to compress in zip format, so you don't have to change extension, to change size!
k: