Compressing Windows Server 2003 IIS logfiles is so simple. Right click on the directory that contains the logfiles Example: c:\logfiles\w32098908a select the Properties, then in the General tab select the Advanced button. Tick the Compress contents to save disk space option. Click OK and then another OK.

This will reduce disk space used to a third, so 100Mb of Logfiles will be compressed to approx 30Mb.

Very simple and very effective.