I subscribed as an Estibot Domainer recently ($5/month). It's frigging awesome. I've been using it to see if I can model Ebay sales. Ebay is so chaotic, I don't think there's much rational behavior there at all, but it's still fun.
Even better! I went to the library to see an Oxford English Dictionary. Wow. There are TONS of single word dot coms not yet taken. However, they may be 500 years old and haven't been used since King Louis. Still, interesting to submit to the Bulk Domain Tool to see the corresponding metrics.
A while ago I bought splendidious.com because I thought it sounded cool, easy to spell and was simply a neat word. No great occurrence or search volume but still nifty. I'm still holding it for a while and somewhat hopeful I can turn a few dollars on it. I actually submitted it to Urban Dictionary and they accepted it. Apparently, their "editors" don't care much about etymology. I thought it might help boost its popularity and hence its investment quality. We'll see. Another weird experiment of mine.