[Margh]

The number of answers there are to that question is phenomenal. Here's one I just thought up:

You stop going between A and B (home and work) for 6 months. You're now either unemployed or working from home; the latter can probably be inferred by any changes in shopping habits. Sell that information to recruiters and they'll know how hard to gouge you in your desperation for a new job.

[lsc]

Eh, I think recruiters already usually have a pretty good idea of how long you've been unemployed, and they already use that information against you; the big problem isn't so much that they low-ball you (it's easy enough to get another job once you have one) but that usually they won't give you a chance at all if you've been unemployed for too long.