Second issue is privacy. Despite (rather useles) efforts by registrars and registries to prevent mass queries to Whois servers, there are _huge_ searchable databases of Whois data. This makes it possible for comptetitors to "spy" on your projects, for crooks to determine your wealth and location, for lunatics/stalkers to be always up to date on your location, etc.
I personally use nearlyfreespeech.net for domains and domain privacy.
Now that namecheap has implemented persistent HTTPS throughout a logged on session, I don't feel uncomfortable mentioning them.
gandi.net and nearlyfreespeech.net are mentioned here frequently, as well (e.g. prior comments here -- vote them up, not me). I don't have personal experience with them.
I don't know how suitable these providers are for "commercial grade" registrations. In my "real" work, other people buy those thing. (I'd be interested in any informed perspectives on this.)
Since writing that post I've switched to using a real, physical address and I list my company's phone number instead. As far as I can tell, none of the junk mail, phone calls and spam I get (which is hardly any at all) are due to my whois information.