I have two images that I'm currently using. This one I use for my lock screen:
And here is the main background:
Both are cropped images. I occasionally swap my backgrounds around, but I'm lazy and only do it a couple times a year. I would use the same image for both screens but I thought it was cool that I could use two separate images so I've never used the same for both.
Aside from the Photon 4g and my galaxy s3, I've never owned a phone that was worth changing images on except maybe my old Razor 2 phone that I custom backgrounds of One Piece, but with the crappy 640x480 screen that phone had no real quality.
I used to always have pictures of my dog as wallpapers, but now I like to stick with star wars or anime images. The photon 4g I had did have some decent looking animated wallpapers, but they always seemed to suck away the battery faster so ever since then I've gotten used to never having any animated images. I'm sure there are probably some good ones out there, but I need to save my battery life.. Its so annoying having to charge my phone at work.
*edit* I fixed the first image.