If I could tell you about a profitable handreg, I'd go ahead and register it myself...
I can tell you this:
- Stick to .com
- 2 words or less
- No typos, or uncommon spellings/abbreviations
- Watch what sells (namebio.com)
- Watch what's going to sell (research/news/press releases/blogs/etc.)
- Stick to what you already know. Look for names in industries/niches that you're interested in, or have knowledge of. These names will still hold value for you, even if you don't sell them. You can also add value to these names, much more easily and efficiently, if you decide to use them one day.
Cheers.