Favorite movie, favorite legendary Pokemon, favorite (primary) type (although ghost and dark are close!), and favorite version mascot at that- if only because GSC were my favorite games before HG/SS existed and even then GSC still has that nostalgia thing going for it... I feel old when I think about it.
Probably because I am. ANYWAY Lugia's pretty much the end-all legendary for me and if I ever make an Ubers team, assuming it fits, you best believe it'll be on there. Runner-ups include Suicune (for personal reasons also it's cool too), Kyogre and I'd say Giratina. Conveniently all of these could pretty much fit on the same team reasonably.
Anyone who knows me can, or already has, guess(ed) what my favorite non-legendary is as they read this sentence. And for those who haven't- Oh yes. Misdreavus and Sneasel were always my favorite since GSC because Misdreavus was cute and Sneasel was cool and I was still a kid back then don't judge me. They stuck forever though and Gen IV rolls around and both of them get evolutions and are actually relatively useable- not to say I didn't use them before, but it always saddened me that Misdreavus' type was Physical and Shadow Ball was terrible and Sneasel was cursed with Special typing when its Attack was the best thing it had... I remember blowing my Focus Punch TM on Sneasel in LeafGreen every time, just so it'd have something physical...
I ALSO REMEMBER WHEN MISDREAVUS COULD LEARN ICE BEAM FROM THE MOVE TUTOR IN CRYSTAL </3
There's also a rant on version exclusives somewhere on the forums in which Ikaru is deprived of Misdreavus in every generation, but I'll spare this topic the anger and sadness.