If you are confident in your masculinity then I would suggest H20 ~Footprints in Sand~ (the anime ending is better than the game), Moyashimon (THAT microbiology anime), Otome wa Boku ni Koishiteru (maidens are falling in love with me), Utawarerumono (its popular in australia), Lovely Complex (you won't see this coming), Hayate the Combat butler (or maid I guess...) and if you are in the mood for the extreme Fruits Basket (WARNING: it has a REVERSE trap).
The above are must see if you are confident in your masculinity. Other notable series in the same "trapped" genre but of someone lesser quality (though not bad by any means) are Princess Princess (gaydar alert) & Happiness (it kinda sucks...)
Also though not major themes other series to check out since I am listing em Gundam 00 (they had fanart of this shit since episode 1), Code Geass (fanart and whole side-episode dedicated), Black Lagoon (the twins are freaking EPIC), Genshiken (there is an epic doujin on that episode), Minami-ke (minor but awesome).
If you are interested in something currently airing and is bound to be EPIC then Maria+Holic is only 1 episode but already made of win.
I dunno if I listed 10 series (though some are double whammies) and dunno if it will be enough to turn you gay but hopefully you will enjoy.