Converting CSV to fixed-width in Notepad++?
Solution 1:
Use the built in TextFX menu.
TextFX -> TextFX Edit -> Line up multiple lines by (,)
I didn't discover this on my own, I found it on sourceforge while trying to figure out this exact question!
Solution 2:
In the meantime I have just found a very nice tool for that. It's called CSVed and available here, with many many nice features. If you hate Excel when viewing CSV files like I do, you should give it a try.
Solution 3:
For TSV files (tab separated) and newer Notepad++ release (either x86 or x64) the plugin Elastic Tabs is very helpful for this. I have it configured for .tsv files and it works like a charm.
Another plugin that maybe helpful in conjunction is CSV Lint, but didn't had the need for it yet. It features conversion between CSV comma, CSV semicolon and TSV formats.