I know Amber Benson didn't get dressed in the most flattering outfits on Buffy, but I remember being shocked at how tiny she was when I saw her a Wizard World Chicago ages ago.
Kevin Smith, on the other hand, looked how I expected. (And I found him just walking nonchalantly though the crowd of geeks at the end of the day with no one else even seeming to notice he was there rather amusing.)
That's pretty much the extent of my celebrity encounters. Summer Glau showed up at the one Serenity fan pre-screening I didn't attend and Joss dropped by the fan table a bunch of us were running at the aforementioned Wizard World the day I wasn't there.
Nathan Fillion: chunky side of normal, refreshingly.
Tarantino: way taller than I'd thought. Looks actually to be taller than claimed 6'1".
Alexis Denisof: waaaaaaaaaay better looking in person.
Amy Acker: actually the only actress I can think of who looks larger in person.
Djimon Hounsou: possibly the most attractive human being on the planet holy crap nothing does him justice, and ita agreed with me so I AM NOT WRONG.
This concludes my infodump on actors I've seen in person and have opinions about.
The only really famous actor I have seen in person close up was Jessica Tandy, and she was about 85 and, obviously, tiny.
Denisof is also much taller than I expected - If his claimed 6'1" isn't accurate he can't be fudging by more than an inch - his eyes were at least level with mine.
As opposed to Christian Kane, who looked me right in the chin with the aid of some impressively-heeled cowboy boots. 5'9" my ass!
A friend was posting yesterday about this scandinavian fellow who is on Game of Thrones and just won some 'strongest man' competition. He's listed at 6'9" and 415 pounds, and my goodness that is a large human being. Ah, here he is: Hafthor Bjornsson: [link]
Nordics always win Strongest Man competitions.
Denisof is also much taller than I expected - If his claimed 6'1" isn't accurate he can't be fudging by more than an inch - his eyes were at least level with mine.
He was up on a stage and seated most of the time, so it was hard for me to tell (his hair! SO AMAZING!). Sadly for Joss, he was next to Denisof, and wow. Contrast.
Entirely non-actor-related, but amusing since flea is here: my brother is 6'2", and I view him as an Ent-like beast. Until last summer, when he was standing next to flea's husband (who is, I think, 2 or 3 inches taller than 6'2"). That is literally the only time my brother has looked short as an adult.
mr. flea is 6'6". He's pretty giant. Unless he stood next to Hafthor Bjornsson, in which case he would look like a tiny little man. (Bjornsson is only 3 inches taller, but weighs TWICE AS MUCH and it's not fat.)
I still feel like I should apologize to the whole family flea about the 7' ceiling in our converted attic/tv room. Since we're 5'3" and 5'7", it never really occurred to us when we bought the house that our tall friends would spend all of our parties flinching like the sky was about to come crashing down on their heads.