Where oh where...
Many public toilets
Halfway up Snowdon
By the side of the stage at WOMAD
All the single digit motorways
In a swimming pool where I was supposed to be lifeguarding
In the gardens in the middle of soho square
In the middle of a girls school hockey field when it was snowing
Several other road side venues
In the sea about a hundred yards off the beach in Newquay (a mate later told me it was well obvious to the assembled thousands on the beach what we were up to)
Just about every car I have ever driven
The toilets of a Eurostar

and...

When I was a teen I was besotted with this girl. We both lived with our folks so opportunities for relations were pretty much limited to the alfresco option most of the time. Anyway, we split up and I was devestated but a few weeks after we agreed to meet up for a drink to catch up. Inevitably (feelings were still quite strong between us) we went for a walk to the local park and one thing led to the other. Moments later we were down behind a bush getting it on for old times sake.
What I later found out from the girl (about a decade later) was that her mum had been worried that she would be upset so had discretely followed her to be pub to make sure she was OK and had then followed us to the park and seen the whole thing.
(Outraged_of_Reading tfs-sfw.com, Mon 27 Apr 2009, 9:26, Reply)