Yep, went to my bookmark for the tools today and it's not there! I can't remember if it was this one or another one that used to give you very loose parameters for calculating Op-amp gains then you could choose which E range of resistors you wanted to use? Well handy for calculating non-inverting op-amp gains with the pesky 1+ !
Please bring them all back TI!
My bookmark for one of them was here:
Op Amp Gain Stage Calculator - Semiconductor Technical Support at Texas Instruments
Gareth