Space pens are the best! - Fisher Space Pen X-Mark Bullet Space Pen w/ Square Top Cap

I've been using Space Pens for 20+ years and they are very well made, write well, and their size makes them super convenient. Whether you clip them in a pocket, on the collar of a T-Shirt in the summer, or keep one in your pants pocket, you always have a pen.
After getting tired of losing mine, l started keeping it in a pants pocket with much better success.
They claim the ability to write upside down and on most surfaces. In my experience this is mostly true, but there are some surfaces, like certain plastics, where they skip or don't write. But overall they write on more surfaces than normal pens.
When the two halves are pulled apart and assembled into a full sized pen, it feels good in your hand and i really like the way they write. And they are MADE IN USA!!
The only con is the price of the refills. Fisher refills are in the $6-$8 range. I generally get them at Staples vs online (Amazon) to avoid Chinese counterfeits. OP sells refills for $7.99, I'm sure those are legit...just wait for a global sale :)