Sharing some pretties with you; urban decay
This is from one of my favorite photo collections (this website has a host of fantastic collections even if you're not into urban decay, so by all means, follow the link for beautiful non-decayed architecture, macro shots, human subject collections, etc.)
I think I like urban decay because I like seeing the process of nature reclaiming what man thought would be permanent. On a more positive note, I particularly like the juxtaposition of architectural components next to natural ones that more often than not inspired them in the first place. I also like how decaying structures start to look more human--buildings become bodies, plaster and tile become skin, iron becomes bone and twisted limb....
To me these photos aren't just sad or melancholy, they're beautiful and peaceful and a little bit magical because they speak to a past and a future at the same time. There's a secret hope that if they've been left alone this long, maybe they'll continue to be forgotten, and you can have this secret through it's natural course--like maybe a developer *won't* find it and realize the parcel of land is worth razing and developing....