Right now I'm using the Korg GT-3.

It's an incredibly reliable and accurate tuner... for Standard Tuning

However, for everything else, it's 100% useless

I'm not a good tuner. The best I can tune accurately by ear is Standard, drop D, and Down Half-Step, meaning I can't even play metal stuff for C tunes, etc.

What's a good tuner that will get be all the different tunings I need?
-Krank Krankenstein JR 50W
-Orange PPC112 w/ Celestion Vintage 30
-Gibson Les Paul Studio (white)
-Gibson Flying V
-MXR Carbon Copy
-Digitech Whammy
-Digitech JamMan
-Boss SD-1
-Epiphone Hummingbird
if you're looking for a pedal tuner, Ibanez LU-20. $40, chromatic, and true bypass
My Strat/Modded '69 RI Mustang
Ovation 1117-4 c. '75
Fender Blues Jr. [JJ Power Tubes, White Grille, Warehouse Speakers Greenback Clone]

#? of EHX Guild
korg CA40 i use it and it's great
Gretsch corvette
Epiphone SG special

big muff pi
crybaby wah
RC-2 loop station

Spider II 15W
Bugera 333XL 212
Look at different pedal chromatic tuners, planet waves or boss would probably be my preference.
Bring back Tabo
Ibanez AFS75/Fender Strat Plus > Fulltone Deja' Vibe > Keeley TS808 MOD+ > Fulltone OCD > VanAmps SoleMate > Metro JTM45
what about those Fender or Korg Rackmount tuners? are they worth $100-$200?

I've seen a lot of people use the Boss pedal tuner but i cant say anything myself.