I have listed some stocks that are plays on rising commodity prices:

AAUK - Anglo American, 14.3 P/E, 0.48 Db/Eq, 1.53 P/S, portfolio includes coal, gold, platinum, diamonds, base metals, industrial minerals, ferrous metals and forest products
BHP - BHP Billiton, 23.9 P/E, 1.32 P/S, portfolio includes aluminum, copper, lead, zinc, silver, nickel, ferrochrome, coal, diamonds, titanium, oil, and natural gas
RTP

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MNMM.ob -
PAAS -
WTZ - Western Silver - no debt, claimed enterprise value is $0.22 per ounce of silver equivalent reserve + resource - see page 20 of a Protues report of Western Silver

FDP - Fresh Del Monte Produce - produce grower and distributor - 6.45 P/E - 0.64 P/S - while produce is not a commodity, it may be possible that produce prices would rise along with sugar, coffee, grains, etc? Even if this is a not a strict commodity play, it sure looks like a good value play.
BG - Bunge Limited - agribusiness, includes soybean origination - 14 P/E excluding special items - 0.16 price/sales - this is a play on soybean prices rising
CRESY Cresud Inc. - Argentine land holder and producer of grains, cattle and milk - not profitable - 4 prices/sales - owns 1 millions acres of land in Argentina, 107 million market cap = $107/acre land if you look at company as pure real estate play. The catalyst would be rising grain and cattle prices leading to increased demand for farmable land. Marc Faber likes this company. I'm not as sure because I don't know how to value Argentine land and because of the high price/sales ratio.

CCJ

NXY - Nexen Inc - 5.5 P/E, 0.73 Db/Eq, 1.18 P/S, Canada based global oil explorer and producer. Strong revenue and earnings growth.
PKN
PTR - Petrochina - 9.28 P/E, 0.26 Db/Eq - oil exploration and production in china, also a natural resource play - warren buffet recently purchased a large stake in this company.
TNT - AO Tatneft - 6.0 P/E, 0.32 Db/Eq, 0.42 P/S, Russian oil producer, extremely large reserves/market cap ratio. Very heavily discounted b/c of Russian political risk.