I would be happy with a "Revenue Domains" section just below the "Traffic Domains" section. All parked, type-in or backlinked domains generating revenue for sale, would be welcome.
I have no opinion on a minimum revenue requirement. The previously mentioned sub-section could be eliminated by forcing a $1/day or $30/mo requirement in the title.
jonathan said:
I think instead of a minimum requirement for revenue, there should be at least 2 months worth of earnings that can be shown so that someone can sell. This would probably help cut down a lot on the pump and dump that some people like to do.
What if your domain is only one week old, already generating revenue and you want to sell? You shouldn't be forced to wait 7 weeks to sell. Once the section is added, the MODS can tweak the requirements.