First of all, some awesome gear in this thread!
I used to be a "Guitar + Cord + Amp" kinda guy because there is a certain purity and focus in that kind of set up. Then I started playing with a locally successful classic rock band covering music from the 60's to 90's and I just had to change my sound in order to capture the vibe of certain songs.
I am also a firm believer that changing your guitar sound alot during the course of a gig is a great way to keep the audience fresh and interested. If you're a "one sound kinda guy" I don't care how good that sound is, it becomes boring after the first set. Yup, even if you're a blues player. So, after a lot of trial and error, I have settled on these effects.
At the top, is a Boss TU-2 and a Korg tuner. I use 2 tuners because some of my guitars have the Buzz Feiten tuning system, and others are regular. Having the Boss TU-2 on their allows me to tune silently with either tuner.
I recently added a Boss GE-7 EQ pedal as an attenuator for my humbucker equipped guitars. When I switch from a Strat to a Les Paul in the middle of the set, I just hit the EQ pedal to reduce the guitar volume a little and the EQ is optomized for that guitar.
The pedal on the left is a Ross Stereo Chrous. I use this for adding a light chorus effect on many songs, especially from the late 70's and early 80's.
Then there's my Analogman King of Tone pedal which is essentially a 3 stage boost/overdrive pedal. This allows me to dial in just the right amount of grit when I need a raunchier rhythm sound.
The Analogman TS-9 Tube Screamer is used for those screaming solo tones.
Next is the RMC Picture Wah. Self explanatory. How can play 70's rock without a wah wah? LOL!
......and finally, the Boss DD-3 Digital Delay. Lots of 80's songs use a digital or analog delay. It really fattens up the solo tones, fills out finger picking parts, and just glazes everything with that big 80's sound when you need it.
I use all this stuff seamlessly and and keep it very subtle. The last thing I want that nasty, swirly/fizzy sound so common on digital modeling amps.
This is what gets me through my gigs!