I'm not sure what you're referring to. A google search for "g10 bulb" or "g10 lamp" turns up just a few small, low-wattage fluorescent bulbs. I suspect you might mean GU10, which is a base used on some line-voltage reflector bulbs. GU10 just indicates the shape of the bulb's base, which gets plugged into the fixture; it doesn't tell you anything about the bulb's wattage, lumen output or candlepower.

yes, I meant a GU10. thanks.

GU10's can be very bright. If your fixture can handle a 50 watt halogen, for example, it would be excellent- depending on the height of the ceiling and the flexibility of the fixture, of course.
The halogen version is very bright for its wattage and directs the light very well.

I bought two of these for the track my wife had installed in our basement:

http://lightbulbemporium.com/proddetail.asp?prod=634200

They are very bright and probably too much so for the piece of art we are trying to illuminate.

Here is a link that might be useful: GU10 100W