Veela!Draco/Harry: A Consummation Devoutly to be Wished (Humor, and lots of it). Also mentioned (in the Veela!Draco discussion) were "Incarus Rising" and "Veela Enigma," no links yet.
Visual humor at Simply Potterific - only about 14 comics done, so start from the beginning. Fan comics in a lovely style. Not slashy. Most of them are gen.
And more humor: The Worst Happiest Day, this time from amanuensis1. Just the kind of over-the-top parodirific humor I like.
The same author has quite a few very good stories out there, but I find I can't read too much kink in one sitting. The one not-to-be-missed is Sanguine, A Serpent Knotted Sable (NC-17). Lucius is fantastic. The sex isn't "hot" so much as it is "thorough." And the plot! Mmf! Post-HBP. Warnings: Non-con, non-con BDSM. But extremely well written.
Hot threesomes? Try Seeker Sandwich (Cedric/Harry/Draco, NC-17), by annella.
I'll mention Perdition and (what I think is its sequel?) Redemption here, because someone said they were "must reads" for a young!Snape, but I'm halfway through Perdition and it's so obviously *not* Snape that it's not really worth reading any more. He's Welsh, well-dressed, aristocratic (he thinks Lucius Malfoy is gauche), and has a beautiful singing voice (and bursts spontaneously into song at Christmas dinner). He's also been sexually abused by his father, but I'd be willing to spot you that one. The rest of it adds up to a boy who doesn't act much like Snape. Did I mention he attends church regularly? Oh, and Sirius is an unredeemed ass, which I just can't abide.
p.s. I saw a picture of Jason Isaacs, the actor who plays Lucius Malfoy, and I was struck by two thoughts: (1) I've seen him in other movies. Weird. (2) The man is extremely good looking. I don't see why my sister thinks so much of Dan Radcliffe - I'll take the men over the boys any day :).