Better!  I want it BETTER!

After a lot of good suggestions from users, I have put together some possible upgrades for this project.  They enhance noise, safety, and performance. 

• The LF353 isn't the best choice for an op-amp.  Although it worked, it has potential for more noise than other op-amps.  With that knowledge, I would suggest the LM324.  It has 4 op-amps, so you only need two.  It's also cheaper ($0.33).  Plus, you can buy it at Radio Shack. (For about 5x more money)
• ISOLATION!  For people interested in isolation, you probably need to put in an analog-to-digital converter prior to isolating.  This will make it easier since cheap optocouplers are only good for digital signals.  If I find a good, cheap way to isolate the circuit, I'll post it.
• Capacitors across VDD to GND may be good.  It may depend on how strong your battery is, and what brand.  Another capacitor from VDD/2 to GND will also be helpful with noise.
• A potentiometer  instead of the 200k resistor will give you a settable gain.
• Shampoo and KY Jelly make a better electrode gel.
• Hopping up and down on one foot makes your heart beat faster.

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