I like to put all of by downloads under my home directory. Then I put my personal executable files in /home/bin and add that to my path (things like unrar, etc). This way, if I do a reinstall, I DON'T format my /home partition. Then I can re-create my username and all of my programs, settings, preferences, bash_profile, etc are all intact.
(~ = home)
~/downloads
~/bin
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