Genealogy website Mocavo has made its indexes and record images for all US census records, 1790 to 1940, available free for everyone—no Gold membership needed.
Use this link to search the entire census or one census at a time. My search for my great-great-grandfather H.A. (Henry) Seeger:
found him in the 1900 through 1920 censuses (here’s 1920):
But even a broad search on just the last name didn’t turn up his 1880 census record. Then when I looked for his wife with just a first name, Prentice (that’s how she was recorded in 1880, although her name was actually Frances), and birth year, I found the family indexed with the last name Saeger.
The moral of the story is that you may need to try plenty of surname variants when you search here.
I couldn’t find a way to download the census record image to my computer, but I was able to take a screenshot of it. This was all without having to register or log in to the site, even as a free basic member.
Can’t find folks in the federal census? Download Family Tree Magazine‘s complete genealogy guide to US census records, just $4.99 in Family Tree Shop.