[bhaak]

For visualization I really like kdiff3.

Or on terminals https://github.com/mookid/diffr with specific settings that use 256 colors for highlighting word differences as well.

But for manual merging I haven't found anything better than ediff. That's the only reason I install emacs on my work machines. Seemless integration into a text editor is just unbeatable.

[funstuff007]

I like kdiff3 better for 3 way merges, and meld for comparing two files.