CultPens also runs a buy four inks get one free sale every once in a while also, it looks like it's currently going on- I like it as an opportunity to try something new if I'm already planning on buying things (I tend to keep a list and order from there once a year or so when I have enough to get)

Ohhh nice. Because I have several past inkvents I could do with more of. Not right now, but in future.