I received a $100 gift certificate to a LHBS from my bosses for Christmas. I had just bought a sack of TFGP from there, stocked up on specialty malts, and just got this season's hops in the mail a month or so ago. So, in the interest of further driving my girlfriend crazy with things for the ol' homebrewery, which do y'all think would be the better use of these pennies from heaven? The gift certificate won't cover the cost of the stir plate, and I'd still have to purchase the flask, stir bar, and foam stopper. I've also gotten into the trend of using dry yeast for probably 2/3 of the beers I make. However, I do think that having one would be fucking cool. I can definitely cover the oxygenation rig with this money, and maybe have enough left over to purchase enough DME for a short on time batch. What say you?
You can build a stir-plate for hella cheap, or you could get this stir-plate, which is only $44. IMHO, a stir-plate that will get the job done is quite a bit cheaper than $100, and in light of the fact that you manly use dry...I vote for the O2. With the caveat that I would purchase an O2 system that uses pure O2, and utilizes a metal wand...like this.
I would go pure O2 setup before stir plate, because there are limits to the amount of O2 you can dissolve in wort by shaking, but there are not limits to the amount of yeast you can make with simple/shaken starters (given willingness to spend more on DME and time with a simple/shaken starter vs. a stir plate starter).
What they said, O2 set up is only about $50, I would get that, a flask and a stir bar and have money left. Then go with the DIY stir plate.
I'm gonna echo everyone else, buy the O2 and build a Stir Plate. Can't build your own O2 system, trust me, I've tried to figure out how to repurpose items. Finally found the red bottle regulator in a Propane/O2 torch set and pulled the regulator for brewing purposes, but that is still the same thing you are looking to buy. You can make a Stir Plate easily and on the cheep.
I built my stirplate in less than an hour, very easy (and cheap if you have an old computer laying around). A couple magnets from an old harddrive and a fan from the computer along with an old cell phone charger. I mounted the fan on a piece of cardboard, plug it in it is on full speed, unplug to turn off. Cheap and easy.
