Jobs may still be scarce in today's economy, but there's no shortage of nasty IT work -- as the third annual installment of our Dirty IT Jobs series clearly demonstrates.

Some tech jobs are literally dirty; digging around the innards of a data center or running network cables through crawlspaces, for example, can leave you deeply in need of a shower.

[ Also on InfoWorld: For more dirty IT jobs, see "The 7 dirtiest jobs in IT" and "Even dirtier IT jobs: The muck stops here" | Find out which of our eight classic IT personality types best suit your temperament by taking the InfoWorld IT personality type quiz. ]

More often, though, dirty IT jobs put people in tough positions -- like having to explain to a crew of arrogant geeks why the network can't be upgraded the same day payroll needs to run; or why you're not a spammer despite what it says on your business card; or how lying about your company's products is probably not a good strategy for long-term growth. You may be forced to take the blame for a failed project even when it's not your fault or to expose wrongdoing at your workplace even if it puts your career at risk.

Dirty jobs never rest, and neither do the people charged with doing them. Be thankful you aren't one of them. And if you are -- well, at least you have a job. Right?

What dirty jobs have we missed? Nominate yours in our dirty IT jobs discussion thread.

Go to: Dirty IT job No. 7: Email ninja