I like Mr. Kevin Tong. Not only does he make fancy posters, he also makes elaborate blog posts about how he makes them, often including process videos. Nice stuff. He even did an instructional video on how to pack valuable prints to protect them from damage during shipment. (If you're interested, find it here along with plenty of other videos.)
His R2-D2 poster is particularly intriguing. I love the end result, but I can’t help but thinking that making it must have been such a drag! Oh well, Mr. Tong probably couldn’t disagree with me more, so no worries…
Check out the video below and please check out his blog at tragicsunshine.com. Lots and lots of cool stuff there. For more of his work as an illustrator, visit his portfolio.