[PaulHoule]

A few years back I had a job where I spent 50% of my time on a glamorous project and the other 50% doing "internal consulting", which means doing various projects for various people using various toolsets. After that I spent about a year working at job shops, where it was the same story.

In this environment I was forced to use a new language every few weeks... Not usually glamorous languages (say Haskell) but more commercially common (and not so common) languages.

I found that my productivity was definitely hurt by the constant need to re-learn the details of how to accomplish simple tasks, like opening a file or figuring out where they hide the urlencode function.

That can get you into maintenance programming hell pretty quick. Your manager always thinks you're too slow (although other people doing the same job are even less productive) and you don't get respect, don't get a raise, and ultimately the walls squeeze in until you need to move on.

Personally I think the things you can ~do~ with software are more interesting. I think it makes more sense to pick a language that's "good enough" and focus on getting highly proficient.