Removing Permanent Marker

[Bines]

Should you have the need, permanent marker can be removed from smooth non absorbent surfaces by applying dry erase maker over it.

Metal, glass, plastic, white boards and the like. Color over the permanent marker with dry erase maker, and simply wipe it all off.

[Lord Pentecost]

It can also be removed using Mentholated Spirit, White Spirit, Surgical Spirit or even Vodka!

[RJBowman]

I've heard this, but never tried it:

You may think that dry erase markers work by not containing whatever it is that makes marker stick, but I've been told that they actually have regular marker ink plus an additive that keeps them from sticking. Supposedly, you can remove permanent marker by writing over it with dry erase marker and then wiping it off. This probably would not work on, say, twenty year old markings that have set in to the surface.

[Bines]

Yeah. If it's set up 20 years, you may need one of those solvents.

I've successfully used the dry erase technique after a few days.

[Crescat Scientia]

Mineral oil will remove permanent marker from nonabsorbent surfaces.  No dangerous solvents need be used.

For that matter, acrylic paint is soluble in ordinary rubbing alcohol.

I have had recourse to both of these solutions when occasional guttersnipes see fit to attempt to mark up our recycling and rubbish bins.