Cheap Box Sets

I'm surprised you're asking this, but just as a rough price point, I'd say that any brand new box set at $5 per disk or less is probably a pretty good deal. Assuming the sound quality/mastering or remastering are up to par.

Here's another contender:

Zappa - Meat Light - $8.71 + $4 Shipping from Amazon resellers (3 disks) 

I am getting another box of Classical music from Telarc this week, but with pop/rock one just downloads everything for free off bittorent... !!??
how do you factor in the fact that our kids download whatever they want for free??? Napster is dead but they do it!!!??

My best-buy box set ever:  The Beaux Arts Trio's 60th anniversary box.  You can find it for under 2.00 per disc (I got the 60 CD set for 100.00) if you try.  Tremendous variety and consistency.  Don't be afraid to take the plunge on this one.

Got that right tosta , Beaux Arts Trio was a powerhouse group that has never been equaled . Never played a bad note .

As we are onto classical music, I would note there are now many inexpensive but high quality classical CD box sets available, mostly from the "big three": Universal Music, Sony Music, and Warner Classics.

A standout example would be Deutsche Grammophone’s (Universal Music) "The Originals" 50 CD box sets, Volumes I and II, which generally comprise top notch performances by many of DG’s finest artists over the last many years. Selling at around $100 per box -- $2.00 -- per CD on Amazon, these are one of the great bargains of the century (so far).