I don't know what a 'Computer Sign Pen' is vs. a regular 'Sign Pen', but you can get a box (of 12) of the Dong-A Comssa Computer Sign Pens at JetPens for $5.75 (U.S.) They have been marked down from the original price for well over a year, so I took a gamble and ordered them.
As you can see from the review, I was a bit torn by these. They are comfortable, consistent, and if you like line variation, you can achieve it quite easily with this pen. I thought my handwriting looked atrocious - more so than usual, so that was somewhat off-putting to me. If I were one who doodled, and I'm not, I think I would appreciate these much more than I did.
I cannot fault the pen for my lack of drawing abilities, so I will say that I liked this pen, but I would like it more if I had different direction in mind. If you doodle, love sign pens, or don't care about your writing, you should probably give these a chance.
The cap includes a raised portion to prevent it from rolling off of your desk, and there is no clip to speak of.
I did try using the period over the course of a few weeks, and the tip has not worn down at all, so it seems that you will get some good life out of these, unless you have a very heavy hand.
I tried to do the frontal shot of the point (a la No Pen Intended), but I do not have the skills to utilize my camera to the best of its abilities quite yet. As you can see, there are little fibrous hairs that compose the tip, and I do not know what the material is, but it seems like it could be some sort of plastic.
Overall, not bad. I just wish I liked them more for my preferences. I gave the rest to a friend of mine, and he is currently using them for some doodling. I am glad they found a good home.