First of all, the ones that didn't make my top five:
Page 119 - We have the story about Uncle Bilius who got drunk on firewhisky and pulled bunches of flowers out of his - *left to your imagination*. That's not really innuendo since I think it's quite obvious even to the littlies what's going on there.
Page 140 - “Ron struggled for a moment before managing to extract his wand from his pocket.” By itself, not so bad. But when combined with all the wand=penis implications elsewhere in the book it suddenly takes on a new meaning.
Page 225 - The innmuendo on this page sounds better in all the LJ icons that say 'Hermione pointed her wand at Ron's tent and said 'Erecto!' but I can't go along with this due to the fact that the tent actually belongs to Perkins from the Ministry, not Ron. It's an annoying bit of fact that ruins an otherwise great bit of fun.
Page 313 - I think this comes close, with the light coming out of the Deluminator and going into to Ron, but isn't quite good enough. It would be better if it was coming into Ron, but that might have been a step too far.
And now... My Top Five:
5) Page 14 - After Lucius has given Voldemort his wand: “'Good,' said Voldemort. He drew out his own wand and compared the lengths.”
4) Page 355 - “Harry hurried back inside the tent to find Ron and Hermione kneeling on the floor beside the little radio. Hermione, who had been polishing the sword of Gryffindor just for something to do, was sitting open-mouthed, staring at the tiny speaker”
3) Page 97 - Ron has just given Harry a book about how to
2) Page 422 - Hermione, after taking the Polyjuice Potion to turn her into Bellatrix: “'She tasted disgusting, worse than Gurdyroots! Ok Ron, come here so I can do you…'” Double innuendo that actually works as a single implication as well. What more could you ask for?
1) Page 337 - Hermione tells the boys that universal truth about men: “’Wands are only as powerful as the wizards who use them. Some wizards just like to boast that theirs are bigger and better than other people’s.’”