Well, there are so many good ones out now, that its hard to pick a favorite. I can only speak about the ones I own.
The Griffith Patrolman is an incredibly versatile knife. With neck, belt and IWB carry, it should suit any need. Workmanship is outstanding, and is able to handle many utility type tasks. Its classy looks are a bonus as well.
Raker 'lil blue II'. Ray Kirk makes some great knives. This little neck knife is very easy to carry. It is solid as a rock, and sharp as a scalpel. You cant beat his prices either. This knife is worth much more than he charges.
Rekat utility neck knife. Nice little production knife. I dont believe that they are made anymore, but if you can find one for a good price, its worth it.
Livesay Woo. This one wont win any beauty contest, but for 25 dollars, its a pretty good deal. Its one that you can use pretty hard, and not be afraid to abuse it, as the cost is low enough.
Richard