The header image (here and on my Twitter page) is Nighthawks, made in 1942 by Edward Hopper. My Dutch site features a less well-known scene of social interaction by Hopper: Chop Suey, made in 1929. Both images are in the public domain.
For simple visitor statistics I use Matomo, an excellent open source alternative for Google Analytics. Data is anonymized and never leaves the server. Some custom downloads (e.g. my CV) are managed with Download Monitor, making it easy to keep track of downloads of periodically updated files.