I'll tell you, there is no item of clothing more comfortable than jeans, as long as they fit right.
I've
never found of jeans that I feel comfortable in. Resultingly, I never wear jeans. I previously owned one pair of jeans, which I cut into uber-short jean shorts for the short film I made for my French class. But, beyond comfort, I just look ridiculously stupid in them. I've always been very sensitive when it comes to clothing, though. I cut all the tags out of my t-shirts until I was about 12. I've never felt comfortable in ties, knit sweaters, or collared shirts with the top few buttons buttoned... I'm just very awkward.
If you're a lanky, underweight white man, I don't think any article of clothing is more comfortable than a pair of cargo pants.