Are Android chargers universal in terms of power (Voltage, amperage)? I would like to buy a car charger, wall charger and USB cables for my Samsung Intercept. However, $20 for a charger seems expensive and I want to avoid getting ripped off. The Samsung Intercept Manual doesn't show the specs for the charging port on the phone itself.

Can I use any Android charger with any Android phone? Does Google require Android manufacturers to follow a standard for charging the devices? Or do most Android devices follow their own proprietary standards. The form factors (Micro-USB, Mini-USB) and voltages (~5V) seem universal, but I'm more concerned about amperage. It's not unheard of for some chargers to ignore the USB 2.0 standard. Do some chargers try to force 3000 mA down the wire to supercharge their devices? If so, that could destroy a device which is intended to receive only 500 mA.

I can charge the my Android phone using a powered USB port on any computer. How many milliamps does this provide? I read that USB 2.0 will provide a standard 100 mA or 500 mA. Are there another standard amperes which are used for charging?

I found what appears to be a generic wall charger for any Micro-USB device. The product description doesn't say how many mA this provides, but from the comments it appears that this charger provides 950mA. Which this overcharge my phone?
Some devices use USBMicro, others use USB Mini. Like any device, it depends on the voltage that the device can take. But for the most part, AFAIK, as long as the charger is the same plug type (micro, mini, etc.) then yes it can work. 

A lot of the chargers that use USB plugs output the voltage that a standard USB port would (between 4.75 and 5.25 volts). If this is the case, you will have no problems. The only issue, when you use USB to charge, it is usually a slower charge then using a wall charger.