According to Ajaxian,
Chris Zip otrelizil
Resource Accelerate , filter for J2EE applications, which allows to improve the performance of applications using DSS, Java Script and image shared.
Caching Header Directives - noticeably reduces the number of server requests when using shared resources.
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Gzip Compression - sobsno, GZip compression (especially relevant for JS, CSS - 60-80%)
JavaScript Compression - Dojo ShrinkSafe implementation