Well I'm certainly not shy!
Not sure about a top 5 but it doesn't get a lot better than doggy anal for me and with the guy a good height over the girl's arse so his cock thrusts vertically and not a bit more horizontally, which porn guys often lazily favour.
Also 1 I think I've only seen once....Jules Jordan and Tory Lane in one of the Weapons Of Ass Destruction series....he comes on her heels at the end of the scene. Awesome. I've something of a heels fetish so that'd do it for me every time. More of this please!
And guy to girl ass-licking. Not enough of this and the guys generally don't look too enthusiastic. I want to see a real bunch of slurps rather than just kinda sticking the tongue in a bit like most do. The girls tend to be better at the ass-licking I find but that doesn't turn me on so much.
Quickly going from a static opening to hard sex is a good one. Straight to anal in a real lust rush (and ideally with the girl fully or partially clothed) is normally a winner.
Like I mention in that other thread, the multiple cumshot is a lost art that always did it for me.
OK that was 5!
Not really that big on DAPs or ATM personally but that's just me.