They make me grin like an idiot XD In a how-can-they-be-so-adorable way. Bradley & Colin (Merlin) and the cast of Psych have that effect on me as well. And Matt & Karen (Doctor Who, of course). I just love it when actors get along so well and make me wish I was cool enough to hang out with them *happy sigh*
Man, I wish I had my Photoshop right now. Screencaps. Icons. So cute. Can't stand it. FIXING EACH OTHER'S TIES.
( While I'm here I might as well mention the most recent episode of White Collar )