$75 gift certificate...what would you buy?

As a going away gift from my previous job, I was given a $75 gift certificate to a homebrew shop. I'm not sure what the rules are here so I won't mention the name but it's one of the big ones.

My current setup is your typical Denny Conn style MLT all grain setup. My kettle is bigger than I need. I have a grain mill that I'm very happy with. I keg my beer and have a three tap kegerator with Perlick taps. I also picked up a refractometer. Basically, I'm very happy with my setup as it is so I'm kind of at a loss for what to buy.

I'm living in a one bedroom apartment with a girlfriend, a dog, and all my brewing equipment so whatever I buy must be small. With that in mind, what would you buy? The default option is picking up ingredients but I was kind of hoping to use my "found money" to increase the brewery gadgetry.

I would buy an O2 system.

pH meter...

+1 on O2 something to do easy yeast starters might be good too

A yeast starter setup if you don't have one or some form of fermentation temp control if you can.

How are you chilling? You could upgrade to a newer chiller, sell your current one on here, then go with ingredients from that sale. Win win.

If you have all the suggestions above...just buy ingredients! ...mmmmmmmm....beeer!

Yea, if you're not making starters with a stir plate, that's a nice small addition to have.
Stir plate + large erlenmeyer +good stir bar is a nice luxury, as would be an oxygen system.

I assume you've got your fermentation temperatures under control...

apart from that, a fancy pH meter would be cool, one with ATC and dO2 would be super awesome.

4 way gas distributer.

Temperature control is one of the big downfalls in my brewing. I don't have room for a fermentation fridge or anything that takes up much room. Do you guys know of a way around that? I was thinking of putting a thermostat on a brewbelt and fermenting outside on a balcony. Have you ever heard of doing something like that?

As far as the rest goes, I have the yeast starter setup but a stir plate might be good. O2 and pH meter might work out well. I currently have a small-ish immersion chiller. I've been thinking that it might need an upgrade if I move on to 10 gallon batches. So many choices!

If you can find some small box, or even a cheap mini fridge, an aquarium controller, or a Johnson controller would allow you to keep your beer in range out on the patio. A small heater or even a light bulb could probably work if the box has some insulation.

A pH meter would be good if you wanted to get into playing with water chemistry.

A stirplate is great, but you can build one for less than $20 easy. If you have a few basic tools that is.

An O2 system is nice. You could get away with an aquarium pump and an inline filter though. Almost as good.

Honestly, if you think you need to tweak fermentation, I'd start with the temp control first. Pitch rate and O2 are easy enough to fix without spending any real money. At least until you get the temp controlled.

Well, that settles it. If you don't have fermentation temperatures under control, then you should have no other priorities for your brewing before that gets taken care of. Most of the big homebrew retailers sell a temperature controller for about that money- go find a cheap minifridge that will fit your carboy, on craigslist or even new. Shouldn't take up much more space than your carboy does now, either.

I would not spend the money on temperature control from a homebrew store. That money will be better spent on something you cannot get cheaper outside the homebrew shop. I would go with a pure O2 system, or yeast management stuff (flasks). I would also get little stuff that you never want to spend the small cash on but are nice to have (book, new airlocks, pH test strips, SS baster, new tubing, or a new fermenter).

I'd buy a bunch of specialty grains and go wild.