I was given a Cello Silke pen in pink, and I LOVED it. It is so much better than any other pen I have ever had. It writes very smooth, and is comfortable to hold. I had trouble finding them because I couldn't find anything about them online. The company (Cello) doesn't have a website online.
I happened to be at my local Wal-Mart Supercenter tonight, and found them. The were not hung on pegs like most of the other items in the pen and pencil aisle, they were on the shelf down near the floor. The are in a container - a cardboard back w/ a clear plastic front. There are 24 in a package, 6 pink, (my personal favorite) 6 purple, 4 blue, 4 yellow, and 4 green.
Good luck in your search...it will be the best $2.44 you have ever spent on something to write with.