Look what I found underneath:


This was on my low mileage, well looked after(ish) example. Imagine how bad this could be on some of the higher mileage hacks that are floating about. This could even be where Bailes rotten roof started off originally.
Hopefully I've found this in time to get something done about it, but going by what someone once told me about the only way to get rid of rust properly is to get rid of the metal, this could be the beginning of her end.
Anyways, now I've started us off, has anybody else got the same under their rubber, or could anyone share any other potential rust traps they might have found on their cars?