ZIP tools were really a great innovation within the last 10 years. They are able to compress text by factor 10 and most EXE files by about factor 2. The most often used tool is definetely Winzip. But, as it is shareware (and not too cheap for everybody in your company), you can find a very useful freeware with similar features as well:
Easyzip 2000 which can be free downloaded and used at one of the following places: (below 2MB !)
Download from "TotalShareware.com"
Download from "TheFreeSite.com"
If you are looking for a tool, that has highest compression ratio (30-70% better than WinZip), have a look at 7-Zip!
It can even work with most RAR files in opposite to Winzip.
Winrar - the famous tool for the rar files - would be charged again ...
So, have really fun with this nice, tiny, free & very useful tool Easyzip 2000!
As SAP customer, you will know CAR (car.exe) or SAPCAR (sapcar.exe) as well. These tools are similar and are having the same compression ratio. They are used for all SAP patches and deliveries, because this tool is available on any from SAP supported platform. It uses an Unix similar syntax as e.g. "sapcar -xvf file.sar" for decompressing the files. If you are having CAR or SAR files to decompress, you have to use this tool, as Winzip, Winrar, Easyzip 2000 and so on are NOT compatible with these files. Up to 4.6B SAP used CAR.EXE. This tool can compress ("car -cvf file.car ...") and decompress CAR files. As of 4.6C this tool was enhanced and then renamed to SAPCAR.EXE. This tool can still work wtih CAR files, but is able to work with the newer SAR files as well. So, you may want to download SAPCAR instead of CAR.
You can download the latest version of the CAR or SAPCAR in the SAP Service Marketplace. As the binaries are different for each platform, you should have a look at the following link:
Download CAR or SAPCAR in the Kernel Patch directories
If you should have ideas for other such useful tools, please just let us know at the feedback area.