If com is taken and no others, I wonder if it's really worth it. If com/net or com/org are taken, the third is often a good deal, as well as adding info. I usually only register .biz if all other TLD's are taken, and at least one or two is developed (not parked or PPC).
I would ask the question... is this for your personal/business use?
If it is... then buy everything that is left... domains are cheap and you don't have to worry about anyone but the .com stealing business from you...
I like .net's .... and .org... .biz and the others will HAVE to catch on it time... there is no other choice... but how long will it take... how many YEARS do you have to hold on to it???
Shawn
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I asked for a .com and got a .screw
I'd agree with freak... and if it's an organization, then take the .org version... it really depends... .net isn't always the second to .com in various ways IMO