One of my favorite pairs of socks, Juta's Stockings by Nancy Bush, suffered a double blowout at the heels. Sadness!
I considered darning the holes or possibly knitting over them, but realized the yarn at the heels had become like the proverbial old wineskin, so worn that the stress of patching would only cause further damage. So I started a new pair, this time in black.
Black is the new purple!