Took down some curtains yesterday, and noticed the plastic hooks were a little grubby, as were the plastic brackets attaching the rail to the wall. Removed the lot and cleaned the real, but the hooks and brackets I dumped in the cutlery thingy, in the dishwasher. Came up just like new! [2]
At the same time, I put the lid of our telephone junction box (connection box) [1] in the dishwasher, which removed most of the paint applied over the last fifty years! I will leave that in for another wash.
[1] BT35A clearly marked GPO, so been there for a while. Incoming cable has 7 wires, but only two are connected. A few more inches of cable connect the BT35A to the master socket. Most odd. [2] The dishwasher and washing machine are also excellent for cleaning grubby Lego. Does not do the sticky labels many favours though :-)