That's why when I list languages I have experience with, i try to put a self assessment in proficiency as well. so instead of just saying "C#, C++, Ruby, PHP" i'll put "Expert proficiency of C#, advanced proficiency of Ruby, and PHP, and working knowledge of python, and TCL"

so if someone is doing a keyword search, i'll still show up, but when someone is actually reading the resume they can say "oh he's a C# and Ruby guy" I'll also mention the language once in the experience section to demonstrate how i used it.

Generally speaking though, as i've searched for more senior positions I've toned down the specifics of the technology, and concentrated more on the results I've achieved.