Chicago Computer Club
Chicago Computer Club provide full I.T. Service for all kinds of computer users. Provide affordable computer equipment and computer service to Home user, provide IT solutions to business user.
Here is the place the logo will be used: http://tmp.cccc.us
People has computer problems.
No 3-D style logos. 3-D logos are dated, very 90s. Also they are harder to reproduce in multiple formats (on schwag, in print, etc.). Any truly good logo (IBM, Fedex, Coca-Cola, etc.) holds its own in simple black and white - color is simply cosmetic. 3-D logos rarely meet this standard.
2-color logos are cheaper to print; anything more than 3 colors and you pretty much lock yourself into digital printing which means colors aren't likely to match from item to item. That's another argument for a logo that looks good in black and white.
With symbols, make sure they have a purpose, and while obvious is sorta good, too obvious will be cliche (e.g. cogs in the case of this contest).