After chasing the Wheat spread with limit orders for a couple of weeks, and sitting through a "massive" (relative) drawdown I closed the last 3 contracts of the spread today:
Sold 3 May 08, Bought 3 Sep 07 ZW Wheat @ -14 1/4
The average price of the total five contracts was -10.55:
Sold 5 May 08, Bought 5 Sep 07 ZW Wheat @ -10.55 - CLOSED - LOSS 3.063 usd.
I'm unfortunately in a bit of a hurry, and see there's four pages to read, but I only have time to say this important thing: The stoploss here was GROSSLY VIOLATED!!!! Now you can hound me, call me a bad trader, or whatever you want

It worked out in the end, but the September Wheat could have continued to soar and the dog May contract could have stayed without attention for 3 more weeks, at which point one (I) would have been forced to close it at -30, -40 and so on... You get the picture.
A brief comment on the energies: The gasoline spreads have been lingering around stoploss for quite a while. The Heating Oil has been down around stoploss, but it's kind of bounced back and is just so illiquid (wide). If it continues down below the 0.500-0.600 area I will kill it - it's been kept since I plan to keep it until Oct 11th.
I'll try to post more in the weekend - the last couple of weeks have been so busy in equities that I have only casually watched the spreads.
EDIT: And yes, I really do hope September Wheat drops like a rock towards the close after the crop report!