So, yesterday I slipped on a wet floor in a train station and bruised the hell out of my knee (fortunately my favorite jeans survived, however!). The shoes I was wearing at the time are my new ankle boots, which I have worn quite a bit around town so they are already fairly scuffed up on the bottom, which is supposed to help. However, I suspect the reason why I fell is because the heel part is made from some kind of hard plastic, which is still pretty slippery.

Has anyone tried any of the various stick-on grip tape, etc. for shoes like this? Or had a cobbler do something to make them more stable? Bonus points if it makes them quieter to walk in -- I am imagining some kind of stick-on rubber sole but I don't know if such a thing really exists.