I’ve always thought these tube-wringers were a waste of money, but a friend has one and now I find them really useful. Its amazing how much paint you can still get out of an “empty” tube.
My apologies to the tube wringer inventor for having ever doubted your genius.
One thing to note is that, apparently, the cheaper plastic models are better than the more expensive metal ones which can rip the tube if the paint inside is stiff (e.g. hand-ground colors or Old Holland lead white).