Large text file viewer

I'd like to be able to view the contents of a very large text file. A bunch of people on here have asked the question in the context of an editor, but I don't need to edit, just view. I'd like to be able to jump to any point in a multi-gigabyte file instantly. (This should be possible if accurate line numbering is not required.)

"less" sort-of works, but the interface is clunky and the commands are hard to remember. Something with a decent GUI would be better.

Anyone know of such a thing?

glogg - Smart interactive log explorer using Qt

Edit: glogg can easily be installed using your favorite package manager after first enabling the universe repository. Once this step is complete you can simply issue the command apt install glogg or in the usual fashion with the software center.

Main features

Runs on Unix-like systems, Windows and Mac thanks to Qt
Provides a second window showing the result of the current search
Supports grep/egrep like regular expressions
Colorizes the log and the search results
Displays a context view of where in the log the lines of interest are
Is fast and reads the file directly from disk, without loading it into memory
Follows a log that is written to disk in real time
Allow to insert marks in the logs to interesting lines
Supports vim/less like keyboard commands to move around the file
Is open source, released under the GPL

Sources: http://glogg.bonnefon.org/description.html