I've played quite a few Builds on the Site, though Ponty's Paladin is one of my long time favorites.

I also quite enjoy playing most of the Dunmer orientated Builds, the Telvanni Wizard by Adrik and Devotee of the Ghost Snake being prime examples.

Curse Never Dying's build Riften's most wanted

I can't even remember how I first came upon this site - probably someone linked to it from the Bethesda forums.  But I do remember that Ponty's and Mason's builds were quite an eye-opener.  I loved how they presented them as characters with strengths and limitations; I also deeply appreciated the D&D vibe that crept in a few of their builds.  It was those 2 guys who got me into the site, kept me around, and got me thinking of the game in different ways.  

Probably the closest I've come to playing a build is NoSnakesaLive's Demonhunter.  I didn't do it exactly as presented (due to some obsessive need to "make it my own thing"), but his presentation was an absolute knock-out.  

Lately (though I haven't gotten around to it yet!), Phil's & DB's Bull of Kyne has grabbed my attention.  I definitely look forward to giving ol' stompy a good playthrough!

I tend to take inspiration for my own builds rather than playing anyone's straight. The closest I've got to playing anyone elses build was Paul England's The Clever Man, which was what got me into this site. That's the build I printed out in all it's many paged glory, telling my husband he HAD to read it. That's the build that got me thinking of Skyrim in a different way. Then I went and sort of played it, but mixed it up a bit, and ended up not getting very far because it was too dark for little old me. I can't do necromancers. 

Oh, and I tried Noodles Kynaren Ranger, but ended up remembering why I hate archery/magic builds.

Really, it's no fun for me reproducing what someone else has created exactly as written and I can't imagine doing it, because for me, character creation is the whole of the fun. I almost enjoy mulling over characters as much as playing the actual game. Which is not to say I don't get a HUGE amount out of reading builds - there's a number that have been huge eye openers and inspirations. Too many to link to. The latest one to really grab me is David Okine's Desert Runner, but rather than a Redguard who delves Dwemer ruins, I'm going to make a Breton who delves Nordic ruins. Apart from that it's the same build.

If I ever get a chance to sit down and finish Albino's Regenerator, I'll be running something very akin to the Desert Runner as well... looks to be good fun :D

Right now I'm playing Ponty's Shaper build, a werewolf mage. I always have an itch to play magic classes, and I found myself loving Werewolf combat while play testing a build of my own. I've tweaked the build just a bit by scaling back the number of perks sunk into Destruction and Conjuration for the sake of adding in Alteration perks to further enhance the werewolf/play with Telekinesis. I lose some sustainability with upper level destruction magic, but I can still spam lower level spells with impunity while having added flesh spells to throw on alongside the cloak spells prior to shifting. I've also played through Vlad the Inhaler's Cutthroat build pretty extensively as well. It's been a lot of fun to run around with. All that stamina is pretty crazy.