Try something low on the Glycemic Index, it'll keep you feeling fuller longer and you won't have the urge to snack as opposed to eating foods that are high on the GI.
Peanuts are a great example. Apples, vegetables, etc..
http://www.lowglycemicdiet.com/gifoodlist.html
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Additional Info: Foods low on the GI help to increase HSL, which aids your body using stored fat for energy. Foods high on the GI will cause your insulin levels to spike, which causes something called LPL (creation of fat), and that actually takes fatty acids from your blood and stores them in fat cells. The more LPL takes place, the more you feel the urge to eat sugars, etc.. (which leads to a nasty cycle)