I just stumbled on easygsp, which aims to bring Groovy/GSP to more people by taking the dependance of a Java app server out of the equation.  I would like to take a closer look at this in the next week or two, but if anyone has any experiences with this so far, please share them with me.  groovy-lamp looks like another similar project, but I may be confusing the goals of each.

Tiago Fernandez has a nice writeup on a benchmark he did between Groovy, JRuby, Rhino and Jython.  The verdict is generally a tie between JRuby and Rhino, with Groovy generally a second or third and Jython looking to be in last place on all 4 benchmarks.  Personally, I would have liked to see Groovy 1.7 benchmarked instead of 1.6.7.  Tiago acknowledges this discrepancy but points out that the 1.7 release notes don’t make any mention of significant speed improvements for 1.7.  Here’s hoping that’ll change in the coming months, and the Groovy 1.8 (or 2.0?) will one day be the fastest around.  :)