If you place a boat on a railway, and then push a minecart into it so the minecart is in the boat, you could travel on normal rails very fast, and without using powered rails.

To move forward you have to press the backwards key, in my case the default is the "s" key, and then you will move forward. to move backward press the opposite key, "w" and it will move backwards.

I demonstrate this glitch in a video i made on youtube:

https://www.youtube.com/watch?v=va-kK61FtZQ

Works on versions: Snapshot 19w40a,1.14.4,1.13.2,1.12.2,1.11.2,1.10.2