Your title mentions "Linux console" but your question mentions meld, which is a GUI application. It might help answerers if you could clarify this.
In GUI apps, meld is still pretty much the standard. It works well, it's reasonably pretty and intuitive.
If you're really limited to using the console (i.e. text-only) then apart from the diff utilities built into editors like vim and emacs you could also try the original command line utility diff. I find it very useful to use the -y option to display files side-by-side, and there are other options I've used to display "unified" diffs and to precisely set the amount of context around matched differences. If you pipe diff's output into less you can browse with fair convenience.
If you're comfortable with git, you can also use git diff to generate a patch for you. It'll usually give you nice colors, page to less, and output the unified diff format by default. It'll work regardless of whether the files are part of a git repository.
git diff -- file.a file.b
If file.a and file.b reside in a git repo and are untracked, you'll need to supply --no-index:
git diff --no-index -- file.a file.b
because git will diff against the index by default.
I started to rebuild xxdiff in the console (since I've entirely switched to tmux console development) into a new Python-based single-file tool I call "termdiff". I ran into curses compatibility problems so I put this on the ice for now, I just need some time to fix minor issues with filling empty space, but it currently spits out output that looks just like xxdiff and you can pipe that into less.
In the meantime I'm using a customized Emacs config and ediff, but it's a little sluggish to start, I'd still like a fast-startup dedicated diff program in the console.
