How about "Domains with Revenue" for sale? It's very difficult finding domains for sale with revenue. I know a site may only have 50 UV but make $5+ a month. You can't find that domain for sale in the "traffic" category and you may pass up looking at the thread in all other listings if it's not a name you're familiar with. If you're specifically looking for revenue domains and don't care of the name or traffic then a forum for them should make it easier to find.