I'd considered upgrading to a fancy pen like a Mont Blanc or a Waterman, but all the places around here had the pens in plastic cases, and I really don't want to spend $40 on a pen I can't try out first. And in any event, all those pens are unitaskers; I really don't want to have to carry around seperate pen, pencil and stylus.
I started to buy a Cross Matrix at Staples, which supposedly has 5 functions and "only" cost $20, but looking at the box, it's apparent you can only chose 4 of the 5 functions (you can have the black gel pen OR the highlighter, not both). I've had a Cross pen with a sylus before; it wasn't very well designed (there was no cap over the stylus point), and this one appeared to be just as bad.
Then I found a Yafa Quadro for $15 at Fry's. It's got a ballpoint pen, a highlighter (which is really just a ballpoint with bright orange ink), a pencil and a stylus. It's got a nice heft and balance to it (I hate pens that are too light), but I soon found that the ballpoint rather left something to be desired. I returned to Staples to buy the Matrix when I noticed that Fisher made a "Space Pen" refill for this particular pen, and for only $2! I love Fisher pens; they write so easily and this refill was no exception. Now I'm quite pleased with this pen.