Game you've won with the lowest odds?

My top 3:

Orcs Must Die 2 Complete Pack - 1:1840
Guacamelee! Super Turbo Championship Edition - 1:1692
Castle Crashers - 1:1554

Dark Souls III ;)

1:1499

1052 entries on Tomb Raider Collection. :3

1:5575 Wasteland 2 :D

1:864 shattered planet

To The Moon with 619 entries and I won
I also won Take on Helicopters Bundle with 1,046 entries, but there were 3 copies so to be exact I like to think that as only 348 entries :P

1:1837
Alien: Isolation

All giveaways I've won are below 100... One was a dev gib xD

the only game that I won was Ampersand
1:561

1/953 second closest was798

Sniper Elite 3 with a 1:5746... yup... :D
Although, in reality my lowest odds were with The Witcher 1. With a 1:6!

Worst odds were 1:4,395 for Thief. The worst part is, I entered it thinking it was the original, and didn't realize my mistake until after I had redeemed the key.

Best odds were 1:2, or 1:6 if we don't count DLC.

1:1434 :)

Nihilumbra - 1259
Psychonauts - 1139

I got very lucky two years back, with newly released Metro: Last Light from CG himself... 11,374 entries :) That's 0.00008791981% chance :)

Awesome game, I bought redux pack as soon as it got out because I felt like I still owe something to the devs :)

1:800 i think.
Although i find ones i lost with great odds to be far more funny. XD

Wait, you mean I can actually win something?!

Worst odds - 1:1442
Best odds - 1:1 :O

Just joined recently, but so far:
Best odds in a private bundle group was 1:1 for NotGTAV (first win for 1:1).
Best odds outside a group but restricted to level 3+ was 1:258 for CoH 2 - The Western Front Armies: US Forces.
Best odds without any restrictions was 1:704 for Sentinels of the Multiverse.
Worst odds without restrictions was 1:2581 for The Stanley Parable, but too bad the key was a duplicate and the sender hasn't been active for 3 weeks and blocked me on Steam.

The odds alone weren't that bad on this one (1,271 entries) but I won it on my birthday and I was the last person to enter. Beat that! :P
And the lowest odds I ever had were on a Hero of the Kingdom giveaway, with 1,414 entries.

Grand Theft Auto IV. 1:4006. Too bad it turned out to be fake as a 3 dollar bill.

Canabalt - 1:1877

Resident Evil Revelations / Biohazard Revelations
1:3383