Beyond Compare (commercial)
http://www.scootersoftware.com/download.php
http://www.scootersoftware.com/support.php?zz=kb_removablemedia

UltraCompare (commercial) ("UltraCompare Portable" is NOT REALLY PORTABLE!)
http://www.ultraedit.com/products/ultracompare.html

WinMerge (free open source) (seems to be as good as Beyond Compare)
http://winmerge.org/


Beyond Compare is run by idiots who do not understand the idea of portable software.

http://www.ultraedit.com/company/about_us.html
http://www.ultraedit.com/company/idm_full_story.html

TLDR: UltraCompare is shit. Use Beyond Compare 3 or 4.

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