Former Evernote user here. I use http://tiddlywiki.com/ and its quite amazing. Self-hosted, small, fast, tons of features, superb tagging support. There is no mobile app, I use Dropbox and view it in Safari. Highly recommended!
Another vote for Tiddlywiki. It support tags, search, easy authoring, export to static html or plain text, hosting on a server or on your hd. All in a single file. There is Tiddlyclip plugin to clip pieces of text to your notes.