Alright, I find the presence of a least favorite character list, but lack of a favorite character list relatively shocking, so I'm gonna go ahead and start :D (BTW, same rules as the least favorite, but I'm actually saying it. Tell why you like them and give a piccy :D)
1: Duo Maxwell from Gundam Wing. He just pwns completely whenever he fights with the Deathscythe. That, and he's just a great source of comedy for the series from what I've seen so far.
2: Kukai Souma from Shugo Chara. He's funny, his transformation pwns, and he's cute. if he weren't a kid in Junior High, I'd officially be a fangirl.
3: The character in Shugo Chara I have a right to fangirl over as he's actually a year or so older than me, Ikuto Tsukiyomi. He's funny, a smart alleck, cute, and generally awesome. That, and he plays the violin, which I love XD The fact that he's a cat boy when he chara changes/transforms also helps
4: Shana from Shakugan no Shana. She's just totally awesome, end of point. She's kick-butt, and completely and totally pwns. "Urasai, Urasai, Urasai!" ("Shut up, Shut up, Shut up!")
5: Rima from Shugo Chara. I can never remember her last name, but I love her nonetheless. She is just too cute, and so is her transformation.
6: Lag Seeing and Niche from Letter Bee. She's just awesome. She's adorable and kick-butt at the same time, and he's just adorable period. I'm using them together here cuz the only pictures I can pull out at school are of them together XD
7: Kazuki Hihara from La Corda Da Oro ~Primo Passo~. He's cute, funny, and plays a musical instrument. XD -notices how many of her favorite characters are male/cute/hyper. erm...., anyway...
8: Heero Yuy from Gundam Wing. Not as funny as Duo, but he still kicks butt and awesome, so he still makes the list <3
9: Yuki Nagato from The Meloncholy of Haruhi Suzumiya. She's just awesome XD Plain and simple. My favorite character from Haruhi.
10: Train Heartnet from Black Cat. I'm surprised I didn't think of him sooner XD He's cute, kickbutt, funny and totally awesome. Take note, I seem to love the funny, hyper characters XD anyway -w-
11: Dino Cavallone from Katekyo Hitman Reborn! He just totally pwns, and is cute and clumzy at the same time. That, and I love Enzo(his turtle that grows giant every time it gets in water)
So yeah, that's about it for now :3 I'll post more later, trust me, when I can actually find pictures for them. Some I've had I haven't been able to find good pictures of because of my school's computer, or I haven't thought of them yet XD BTW, these characters aren't in any particular order :D