Regarding the AV referendum, I was in two minds right up until the last minute of whether to refuse the ballot paper or spoil it with an EU referendum message. I decided on the former - mainly because any messages on spoiled papers will get ignored; a lower turnout sends a better message. The chap at the polling station got a little irritated by my request, he tried to insist that I had to take it (no I don't).
Anyway the upshot is that I haven't partaken in the referendum.
Update: If I had chosen to spoil my ballot paper as indicated above, I was going to take a picture and post it on here. However I find, courtesy of Douglas Carswell, that such actions would have been illegal:
NB. Out of interest, I checked with the Electoral Commission before posting a photo of my ballot paper on line. Apparently, it is legal to do so if you vote by post. But not if you vote in a polling booth. It's unlawful to publish information about what happens in a polling booth.