Are there stepup/stepdown converters that you can buy?

[Bushman]

are there current and or voltage converters that you can buy from zetex,or liner tech. or any of those other companies that are ready to use right out of the package. I wouldn't mind spending $20 or so to just buy one and plug it in to a light...

 

[Brock]

moving over to the "Electronics Forum. Batteries Included"