Too many to, count, I have hundreds of games double or triple... some games even in more versions.
Many for different systems (even excluding crossbuy games for PS3, PS4, Vita)... often the PC version for best quality + a handheld or mobile version for "on the go".
Sometimes the physical + digital version for the same system (very often for old retail PC games, where I'm too lazy to get the disc out of its box and the Steam/GOG versions are cheap).
Also many duplicate digital PC games for different PC game launchers (first version on Steam or GOG, then additional versions due to Epic gifts, monthly Amazon Prime games, GOG Connect and many game bundles).
I also have the Collector's box of "Defender of the Crown" including the versions for C64, CPC, ZX Spectrum, Apple2, NES, Amiga, Atari ST, DOS, Mac, "Amiga Extended", Amiga CDTV, Amiga CD 32 and CD-i... oh, and an Android port of the Amiga version for my phone.
And since someone mentioned movies... I bought my favorite movie "Terminator 2" around ten times (beginning with crappy VHS and "Letterbox" DVD versions) and eventually kept six of them:
