I have all kinds of stuff on my walls. My living room is mostly watercolor landscapes, some of them are thrift store finds but a few are really lovely ones I got from my husband's grandmother after she died. Some are very modern and some are more classic.
I also have a couple of wonderful J.J. Mora lithographs from his study of Native Americans. For example, I have this one:
We got these from my husband's father, who collected Native American art and jewelry. I have 6 more prints on the way -- nobody else in the family really cared for these prints but I think they're terrific.
I'm waiting for the rest of the set to get here before I decide exactly where I'll place them. My house has lots of windows and wide doors and very little wall space so hanging them all is going to be a trick!
One of my favorite things is a poster from the 1972 Olympics in Munich that I found hanging in a discount grocery store/thrift shop in the late 70s/early 80s.
I had it reframed and it has followed me across the country, hanging on my wall for the last 40 years.