I use Optinom!
Where do you keep the majority of your domains and why?
I've been using Name.com for a few years now, they HAD free whois privacy, and are overall great with their support. With their recent changes to remove free whois privacy, I figured I'd at least see what other options there are.
Submit Your Proxies @ Proxy Sites.net
I also use name.com and I found it really simple, instead of godaddy.
The support is also good, they has helped me all the time.
The free private who is was only a temporary marketing method to attract more customers. $1.99/year for private whois is not so much but the free version was a dream
So far I'm really satisfied with name.com
I keep the majority of mine at namecheap. The interface is easy to use and very simple; also pretty good prices. They've got the free whois protection with registration also, they say it's for a limited time, but it's been there for as long as I can remember.
I use godaddy.com and internetbs.net. godaddy is to buy .info domains where they will be very cheap. Internetbs.net is to buy .com and .net extension domains where they will be low cost.
Godaddy and Moniker, both.