Using Arduino with higher output devices

Hey guys, I'm sure this has been probably asked already, so if someone can point me to the right place, I will really appreciate it.

Question: I want to hook up one of those large revolving sirens and have it be controlled on and off with arduino.

I know the power output of arduino is too small for a light like this, but is there some sort of a gain i can add to it?

Just for reference, these are the lights i'm talking about

http://www.thinkgeek.com/gadgets/lights/964e/

http://www.amazon.com/gp/product/B0032F305C/ref=s9_simh_gw_p23_i2?pf_rd_m=ATVPDKIKX0DER&pf_rd_s=center-3&pf_rd_r=0871R759M7S5JRKNEHGF&pf_rd_t=101&pf_rd_p=470938811&pf_rd_i=507846

Those small revolving lights usually use a small 3-6 VDC motor (plus the light) to run them. Probably the easiest way to turn them on and off would be to use a relay circuit (plenty of info for that all over this forum, in the playground, on the internet, etc).

You could also drive it with a "large" power transistor or MOSFET; anything that can sustain 1.5-2 amps of current draw should work OK (but measure the current draw first just to be sure).

:)

Great! Thanks, I actually did some more crawling through the forums, and think that maybe i should use a transistor in the light's switch, and let the wall power or the direct USB power them.

But thanks for the other option :)