I have a Marshall BB-2 Bluesbreaker II, which has both clean boost and "blues" modes. The blues mode does a nice job of adding just a bit of dirt without messing things up.

 
I've got one of these Bluesbreaker II's as well, Drew; I like it and think that it does its thing pretty well.  I have a TS-9 that just has never really done it for me.
 
I just got this OD pedal a couple of months ago, at the recommendation of Herb.  I am liking the smooth overdriven tones that I get from it as well.
 
 

Don't forget about Keely pedals. He makes several boxes that are for just clean boost.

I have a drawer full of overdrives and distortion pedals. I pretty much just use the POD HD500 these days but there are two overdrives that sit out where I can grab them. One is a modified Boss Super Overdrive SD-1. I collect the Boss pedals because they were the first "PRO" (lol) pedals I could afford when I started out.
The other pedal is fairly new to the market. The Electro-Harmonix Soul Food. It is supposed to be an assembly line version of a Klon Centaur. I am pretty impressed with it sound-wise and it only costs about $75.
I have always had to have at least two overdrives on my pedal board. Mainly because of flexibility for recording and most groups I played live with played such a variety of material it was almost a necessity.
Anyway, pedal-wise I would give the Soul Food a shot. I think you will find it to your liking.

I suspect most guitarists who've played for a while end up with a stack of dirt pedals. They seem the most "personal" effect there is, what one loves another hates. For me now it depends on what I'm looking for and the guitar and amp.

The SD-1 is good but has a bit of a mid hump that might be too much on top of a tubescreamer's mid boost. The SD-1 also compresses. Basically it's Boss's version of the tubescreamer circuit but with asymmetric clipping and a bit more transparency. Straight from the factory they're pretty versatile, cheap and have been around for ages. I much prefer them to the tubescreamer. The slight differences from the expensively modified versions don't make much difference to my ears and fingers. Though if you use humbuckers snipping the C6 capacitor off the pcb (it acts as a low pass filter which isn't really needed) can open up an SD-1 and reduce the nasal tone nicely.

The EHX Soul Food is, as Sidroe says, very good indeed. Nice buffer you can choose to use or not, great touch sensitivity at low gain settings, with a bit of compression and mid boost at higher gain. Nice blues pedal and stacks after other O/Ds or fuzzes very well. Does it sound the same as a Klon? Maybe, maybe not, but it certainly isn't $1500+ less good. The EHX OD Glove also has its fans (kind of an OCD clone).

My current personal favourites are a Dunlop mini-fuzz face immediately after the guitar. Silicon for 'buckers, germanium for single coils. Run the gain flat out, then as you back off the guitar volume the tone brightens and fuzz decreases. You can get some nice overdrive/edge of distortion touch sensitive sounds that way. Nothing responds to the guitar quite like a simple fuzzface circuit and the Dunlop ones are fine. No need to pay "boutique" prices for a circuit that uses a handful of cheap components.

Then for Tweedy Fender sounds, Lovepedal Les Lius or a clone. Everything from a bit of break up to Neil Young's "clean" tone. Run a fuzzface into it for the Young "spluttering old Deluxe about to explode" sound. For vintage Marshall-on-10 a Catalinbread DLS. Mine's a Mark 1, the current Mk3 is a little different but still impressive. Their HiWatts in a box sound pretty good as well.

Pigtonix Aria if you can find one. Diode clipping similar to the OCD/Distortion+ but with good three-band eq. Very open sound and very flexible. Pigtronix seem to have discontinued it recently for some reason.

The Distortion+ is also worth considering. Not a huge amount of volume on tap, gain starts as overdrive and gets a bit fuzzy when cranked. Has a dreadful bypass so best placed after a buffer.

Truth be told, lots of overdrives on the market are pretty similar - there are some stand-out ones but an awful lot amount to a slight modification to an SD-1/tubescreamer circuit. In the same way there are a lot of slight variations of the fuzz face, Dist+ and Big Muff out there.

Jordan J-700. I also like the Tech21 Comp-Tortion (you have to tweak the comp low). I usually use those two together. The old Jordan is an amazing pedal. It goes from OD to Dist to fuzz. IIRC, Joe Walsh used one on Rocky Mountain Way, it will nail that tone, turn it all the way up and it is Spirit in the Sky. They are getting expensive on Ebay, I saw one last week for about 500 bucks. If you find a good deal on one, get it. The SD Pickup Booster is a pretty cool little pedal too with a good boost and three different "pickup" settings. Oh, the Comp-Tortion has a 21db clean boost it you just use the level and keep the dist and comp turned al the way down. It never seemed to catch on and I imagine you can find one pretty cheap. The compression/distortion combination on it isn't as noisy as that combination usually is. The comp is good and the distortion is the same a Cobain used... I like it, but the J-700 is a real GEM.
 
>edit When I play Fender amps I almost always use a Boss Bass EQ pedal, I have a Boss EQ pedal but the Bass EQ will tame any flub you might get in a Fender sometime. Just drop the lows a little (you can also boost arund 800 and get a little more into a Marshall sort of spin). I use it on Tweed Champs, SF Champs and a CVR with Rajin Cajun speakers. The stock alnicos are ready to flub as soon as you plug in. I put some Weber C10Qs in it but those things are really too loud and too heavy. Anyway... Boss Bass EQ is a revelation with Fender amps, IMO... and it has a boost too!
 
Another note. Since getting a Mesa Mark V, I don't need OD or Distortion pedals, but I did have to read the manual three times!
 
J

bluzdog
I love my Barber Direct Drive. It's plays nicely with my TS.
 
Rocky

I'm leaning toward this pedal as well since I've been pleased with my other Barber pedals.

 
 

 
the tube screamer killer.

but this is better
 

 

my current pedalboard:
 
 
 

 
that direct drive SS is a "Katrina Relief" pedal i bought from dave barber, back when he was doing a katrina fund raiser...
 
it is a super sport, but in a unique package.
 
my go to solo lead pedal.
 

also...
running the DDSS at 18v....
 
a must.