I got some new pens. One of which is a Sakura Souffle pen. I picked it up because it came in, among other colours, grey. Sometimes I like to stray from the usual black & blue, yet staying close to dark ink. A brown pilot G2 springs to mind 
I started to use my new gray pen with much excitement! The ink took more than 5 minutes to dry! I touched it immediately after writting and it smudged. Weird. I went out for the day, came home and when I next caught sight of the Souffle ink, it had indeed puffed up and looks like paint-pen ink! Curious, I googled it and, haha, it even had a product video on the sakura site! Turns out it writes on plastic too.
Admittedly, I am a stationery freak. I have too many pens and notebooks as it already is.
Cool post!!!