If you had to pick a few styles (no more than six, if you can) of hops to keep on hand, what would your list include?

magnum, cientennial, cascade, amarillo, chinook

Columbus, Cascade, Hallertau

I always have these on hands:
Chinook;
Northern Brewer;
Cascade;
German Hallertau;
EKG.
Using these, you can get away with murder.......or almost. At least you can brew a tasty brew!

Saaz
Tettnanger
Willamette
Simcoe
Amarillo
Centennial

Columbus,Cascades, Fuggles, EKG

Cascade
Summit
Amarillo
Hallertau
Sterling
Tettnanger

Simcoe
Amarillo
Chinook

Amarillo
Simcoe
Chinook
Northern Brewer
Saaz
Fuggles

I hate to tell you, but if you didn't choose cascade I think that means you failed lol.

Cascade
Hallertau
Fuggles
Saaz

goldings
chinook
centennial
magnum
simcoe
(do i have to stop listing?)

i'm a hophead

cascade
amarillo
simcoe
czech saaz
magnum
fuggles

"I hate to tell you, but if you didn't choose cascade I think that means you failed lol."

Honestly, I've always found Cascade to be kinda not that great. Most American hops varieties are more interesting to me than Cascade.

Columbus, simcoe, galena, saaz, williamette, hallertauer...with these you can do everything from traditional continental styles to crazy over hopped ipa's and damn near everything in between...

Tettnanger, Saphir, Hersbrucker, Saazer, Cascade, Magnum

Amarillo, Liberty, Warrior and Hallertau

I like cascade because they are growing like a SOB in the backyard right now.
Also, columbus, glacier, Amarillo, Northern Brewer. Love em all!

centennial
simcoe
EKG
tett.
columbus
amarillo

I could get buy with these

EKG, Fuggles, Hallertau, mt Hood, Cascade are probably my most used; but I have no problem swapping them out depending on the recipe or availability.

Magnum, Nugget, Warrior for bittering- especially in 40gal club brews.

No. Brewer, Willamette, Tettnanger

Those three don't do it for everything, usually at least one of them is in every beer I make.
And I've been stockpiling Perle lately.

Simcoe
Centennial
Willamette
Tettnanger
Hallertau
Cascade
Columbus

Thanks for the feedback thus far! For those wanting to count at home, here's a summary after just over 1 day in the forum:

11 Cascade
9 Amarillo
9 Hallertau
8 Simcoe
6 Centennial
6 Chinook
6 Columbus
6 Saaz
6 Tettnanger
5 Fuggle
4 E.K. Goldings
4 Magnum
4 Northern Brewer
4 Willamette
1 Galena
1 Glacier
1 Goldings
1 Liberty
1 Mt. Hood
1 Saphir
1 Sterling
1 Summit
1 Warrior

NOTES:
- Marco, I'm not sure which Goldings you meant, so they were listed just as Goldings.
- Rex_Irae, I just counted the four you listed at the top.

For my own notes, and I'm not included above, I would probably choose Cascade and Columbus (both general purpose American), Hallertau, Williamette, Northern Brewer, and Saaz. I figure with those I could have plenty of American brews, Belgian/German brews, and English brews. I have been getting Northdown instead of Northern Brewer lately as that was what my LHBS had in stock.

Shannon - East Kent would be my choice - goes nicely in the honey basil

cascade, amarillo,