What specific Linux skills employers are seeking? "We've seen good growth in both 'systems administrator' as well as 'software developer'," Melde says.

"We see requests for 'Linux sysadmins' or we'll see it just as 'Sysadmins', where they use a more generic job title, but what they're really asking for is someone with Linux experience to do system administration. Maybe we'll see it is a 'LAMP Stack administrator'."

For job ads requesting open source skills, Dice has seen the following growth since Jan '07, Melde says:

• AJAX: 100%
• PHP: Practically "doubled since January," he says.
• Python: 72%
• MySQL: 50%
• Ruby on Rails: 121%. But this category is "still small in absolute terms," he says.
• Perl: 22%. Perl, Melde notes, "is not so sexy, but it makes the Web go 'round."

The average 2006 salary for Linux professionals was $77,950, which was higher than the national average for all tech professionals of $73,308. (However, this is somewhat misleading, since the national average includes historically low-paid IT staffers like help desk workers.)

If you're a Linux specialist looking for the best paying area of the country, your best bet is--no surprise--Silicon Valley, where Linux pros make $96,578 (but a cup of coffee costs $11.25). Other top-paying Linux areas are Washington, D.C. ($86,882), Los Angeles ($86,618), and New York ($86,305).

Female Linux professionals, admittedly a scarce group (but certainly an attractive one), earn less ($74,263) than do male Linux professionals ($78,412).

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