Can't remember if I saw it on HN or searched for it, but you can search for the hardest solvable freecell games. I drove myself partially insane trying to solve one. Only got about halfway before I caved
(If you don't have access to windows you can run one of those web based windows desktop lookalikes written in JS).
raspo · · focus · HN ↗
noja · · focus · HN ↗
gosub100 · · focus · HN ↗
(If you don't have access to windows you can run one of those web based windows desktop lookalikes written in JS).