Some stats from Google Summer of Code
The Google Summer of Code has a list of accepted organizations. Next to each organization there are a bunch of tags. One can download the all the data as a csv file.
So I looked at the data and grepped it for several keywords.
Here are the results sorted by number of hits.
There are a lot of URLs in the listing that have php in them. counting php gives 45 results but apparently about 20 of those are URLs. That might also mean something.