Where is the best place online to publicize and idea competition with a sizeable prize?

[Tib]

My company is starting a competition open to the public that will go on for the next bunch of months - looking for facebook app ideas. First place is $5k. Where would be the best place to publicize the competition online for free so that more people can submit and have a chance to be selected?

Thanks to all those who have useful input.
-Mike

[BitterObserver036]

Here are top 44 best free classifieds directory for you to publicize your competition online.
Post free ads there and since you have a sizeable prize, optimize your ads by placing featured ads in these free classifieds directory. This way you would get noticed very fast.

Ablewise.com
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GumTree.com
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Skepter.com
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