Games you bought more than once?

Only one, I bought it two times. wasn't an accident : Space Quest VI.

I bought one, then sold it. Then few years later I was missing badly my buddy Roger Wilco.
I think it's the funniest game I've ever played. Huge humor and quite difficult for my age back in the days.

Mafia 1: retail + retail (cause I lost the CD)
The Witcher 2: Steam + retail (cause of the bonuses)

Trine 1+2 and To The moon...bought from steam store,GoG and bundles

Haven't really done that much myself but I have a friend that bought Castlevania Symphony of the Night literally 5 times.

Age of empires I bought a bunch of times, and portal

Portal + Portal 2, had them on xbox before it broke and I discovered Steam. I guess HL2 + Episodes in a way because I owned but I hadn't played them, just watched my brother play them a bit.

I bought Fallout New Vegas retail and then bought the Ultimate Edition on Steam.

I'm going to buy RollerCoaster Tycoon 2 again (on Steam)... when it'll be on sale.

Also I've bought many games more than once via (re)bundles. For example Yrminsul, Hero Siege, Legend of Dungeon, Rhythm Destruction,...

Points at giveaways. Pretty much those. It wasn't accidental. They deserve to be bought multiple times! :D

Portal 2 and the orange box, on purpose :3

Love those games :D

Waking Mars: iPad, PC - I was keeping an eye on the game and it went on sale for iPad, so I bought the first copy and played it on my mom's iPad. Then I got a crazy-good offer on Indiegamestand, so I bought it (and played it) again for PC

Myst series: PC, PC - first played the game at the house of a friend of my father and I fell in love with game. Bought the CD copies of the games when they came out. Then bought the collection on Steam years later, so that I don't have to bother with compatibility. :)

Mortal Kombat Kollection: Megadrive, PC - played the games in arcades and on my Megadrive, then got the Kollection on Steam in a recent bundle.

All the batman arkham games. I owned asylum and city for PS3 and origins for Xbox 360. I now have all of them on pc :D

Inujustice <---- For a friend.
Naruto ultimate ninja storm: Full burst 3: <--- 75% discount on namco if you got 2 games. Well i got 6, 4 of them copies of that game.

HoMM 5: 1) Gold Edition [Retail CD], 2) The Heroes Pack [Steam] - PC

HoMM 6: 1) Deluxe Edition [Steam], 2) Gold Edition [Uplay], 3) Complete Edition [Steam] - PC

Civ 5: 1) Standart Edition [Retail CD], 2) Gold Edition [Steam] - PC

Unreal series: 1) Standart Edition [Retail CD], 2) Unreal Deal Pack [Steam] - PC

Cossacks series: 1) Standart Edition [Retail CD], 2) Cossacks and American Conquest Pack [Steam] - PC

Never accidentally, but...

Final Fantasy VII / VIII (bought for PS1, sold with PS1, bought PS2, rebought VII/VIII, traded them for... something. Yugioh cards maybe?). Also bought FFVIII on Steam recently.
Final Fantasy Tactics (bought for PS1, sold with PS1, bought PS2, rebought FFT, sold FFT with PS2)
Elder Scrolls III: Morrowind (bought for XBox, later bought GotY used, later bought another GotY copy used because this one came with case and manual intact). Later bought Elder Scrolls Collection for PC.
Elder Scrolls IV: Oblivion (bought for 360, bought GotY, sold original copy. Later bought Elder Scrolls Collection for PC).
Final Fantasy Tactics Advance (bought for GBA, traded for another copy from a friend so I could do the multiplayer missions at my leisure)
Tactics Ogre: The Knight of Lodis (bought for GBA. This game was at one point very sought after and was selling for $100+ on ebay, so when I saw a second copy at Gamestop, I bought that one as well. Planned on selling it, never ended up doing so).
Megaman Battle Network 3: Blue (bought for GBA, received a second copy as part of a trade where I got a DS).
Borderlands (bought for 360, later bought GotY)
Borderlands 2 (bought for 360, later bought base game + DLCs for PC just before GotY came out).

Also some games I know I've bought multiple times but don't exactly remember the circumstances: The Legend of Zelda: Link's Awakening / Metroid II: Return of Samus / Kirby's Dreamland 2 / .Hack: Infection / Red Faction

EDIT: Oh yeah I've bought The Orange Box for XBox 360 and later, all the games on it for Steam.

Final Fantasy X PS2 and PS3
Batman Arkham City PS3 and Steam
Final Fantasy 7 PS1 and Pc
Final Fantasy 8 Pc and Steam
Sacred 2 Retail and got another copy from a bundle for steam

3 x GTA Vice City PC Two Disc Drives destroyed two Copies... apparently my pc didnt want me to play it....
2 x Section 8 First DVD stopped working for unknown reasons

and if you want to count that as well 1 x Boxed Sins of a Solar Empire GOTY and 1 x SoaSE: Rebellion STEAM

Batman: Arkham City. Bought the normal game + all the DLC then bought the GotY version. Love that game :)

GTA VC - 5X
Sims 3 - 3X
GTA SA - 2X
Dead island - 2X
Saints row 3 - 2X

can't remember other ones

Am I the only one who haven't done this??

bought void zero from gmg twice when it was on 70 cents lol

None of my double purchases are because of different platforms:

-Starcraft 1 twice, just because.
-Neverwinter Nights 1&2, because I wanted to get rid of the physical copies.
-Baldur's Gate games because I wanted to get rid of the physical copies.
-Farcry, I had it as a cd long time ago but bought it again because I wanted to get it to my collection when it was cheap on Steam (even though it's not a good game).
-The Longest Journey, because I wanted to get rid of the physical copy.
-Dracula games, because I wanted them on Steam rather than GOG.
-I intend to buy House of 1000 Doors Family Secrets, Into The Dark and all Black Mirror games from Steam even though I already bought them from Amazon/Gamersgate. Possibly some others I don't remember right now.
-Half-Life 2, I bought the Orange box after already having bought the regular one.

Retro City Rampage. Once on 3DS, and the other on Steam (only because it was a dollar).