I've been running Newsy myself to host all of my unused domain names.
Newsy takes an unused domain name and turn it into a content-aggregator (i.e. Reddit clone) with lots of features built in including membership, automated newsletters, HTTPS, using GMail for your domain etc.
I built Newsy because I had close to 50 unused domain names but had no time to develop them.
Newsy lets me quickly build sites for my domains and make use of them while waiting for (hopefully) one day that I turn them into a product.