Ditto to Eric's post. We routinely package DVD's for our productions, and generally no more than 500 dual DVD cases. We have a 10 disc duplicating tower, and a higher end printer for printing the case insert labels, plus a Primera disc printer.
The reason I say 'no more than 500', is because we once did a 500 dual disc job, and afterwards swore that we never would again. Taking into account the actual costs of the materials, you can actually make $$. However, you have to understand that your time is worth money as well, and that level of packaging require automation to be profitable, and not send you straight to the funny farm. 5000 multi-disc packages, and I'll guarantee you'll be on the local news threatening to jump from a bridge.
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"98% of all computer issues can be solved by simply pressing 'F1'."
Steve Brame
creative illusions Productions 
