I got a titanium letter opener on kickstarter a while ago, and just wanted to comment on how useful I've found it. I don't use it as a letter opener all that often; mostly for cutting tape on packages.
But this morning I was tossing out a bunch of boxes we used when we moved in (and haven't touched, since), so I needed to break them down. And I pulled out that letter opener, and it made very short work of everything.
And getting all those boxes (probably twenty or thirty) out of the house certainly put me in a good mood.