Some of them are up and running, PR vary from 3 to 5, Other domains are just sitting there. I posted a business/partnership proposal in here, if someone interested.
I sold many domains without PR for $xxx and $x.xxx each. I already sold hundreds of domains, and the first i sold was my handreg and i sold it about one month later for $80. You can live from domain flipping if you know what you are doing. But it is also easy to spend thousands on useless domains which you will never sell, if you are a newbie, so be careful Domains with PR have some constant value, just as tripple premium LLLL.coms for example. I saw many PR4, PR5... domains which i would never buy as that names was really stupid, but they have value just because of their PR. Real domainer would be more likely to buy good name without PR than some stupid nonsense name with PR5 or above.
The key to domain flipping, in my opinion, is to develop the domain into something that's worth buying. A good domain name that is brandable along with an attractive index page and there will be buyers. I buy .info domains for 89 cents, develop them and sell them for $25 - $100. Some people make thousands doing this.