REXPaint looks amazing!
It’s super cool!
I have it working on my MBP, wrapped via WineSkin. Check this out!!
Obviously just messing around, but it was super fun. I can see this being invaluable in making UI assets and stuff.
I want to use it to make backgrounds for my websites. 
OMG, until this moment I forgot that the CSS border tag supports double lines.
It’s time to get retro!
Making a responsive retro WordPress theme has been on my to-do list for years. Maybe playing with REXPaint will inspire.