In my consulting work, I seem to have benefitted greatly from a shortage of people still versed in old-school systems work, heavy C, Perl, and solid knowledge of the esoteric feature sets of traditional RDBMs. There is a decreasing number of people in the market who really know their way around Linux and other Unices as well, and who can bring some historical insight to bear.

I am not a bearded hacker. I'm only 26, but it seems that everyone in my age group has moved onto fashionable web programming tool chains, Ruby, etc. Personally, that's just as well; leaves me with less competition. :-)