Battery Discharger Unit ?

I was wondering if there is such a thing as a “DISCHARGER” for the most common li-ion battery sizes, as I have plenty of intelli chargers and one digi-charger, however none of them have a “discharge” function. If anyone knows of a decent unit of this sort,please let me know, otherwise any suggestions on a unit that both charges and discharges at a budget friendly price would be appreciated.

The most know (and best) one is

But there are a few other, they can be found in this list:

SkyRC has been working on a "super" unit, but it is not released yet and I doubt it will be budget friendly (My guess is $100 or more).