[moutarde]

MetaFilter has successfully used the "pay $5 for an account" model as a means to balance access against exclusivity. It may not be a tech site but considering it's still basically just an open access group blog (with a few bells and whistles) the model seems to have served it quite well.

[snorkel]

Agree. The $5 lifetime fee was all it took to keep Metafilter from being diluted after reaching critical mass. Simple and effective.