I use the MB14 fountain pen, which you can get off forums and such and a 'black pearl' aluminum and steel Dunhill ballpoint. The Dunhill gets lent to people who would destroy your fountain nib. Its steel body also means you can break a window or something with it if need be or use it as a kubaton but is less ridiculous looking than a Surefire or Uzi pen.
I'm not a fan of modern day Montblancs, but probably purely for aesthetic reasons. On the other hand, I have a real affinity for accessories from the 60's and the MB's from that era I think are really fantastic. I've been using a Montblanc No. 14 for the past year as my daily writer/sketcher and I couldn't be happier. For design geeks, it has the added cache of being designed by Albrecht Graf Goertz, of BMW 507 fame.
Stolen google image since I'm too lazy to take a pic: