I've been doing several pieces in cherry and have a place setup in my basement that exposes them to sunlight through a glass block window. I'm really surprised with the color I can achieve quickly. The first pic shows a table top and 2x12 cabinet I am working on. The table has about 3 days under the glass block, while the cabinet has 3 weeks there and somewhere between 4-8 hours of direct sunlight outside.

The second pic shows the area, and a base and top. The base has about 3 weeks exposure, and the top has 4 days.

The finish is one coat of tung oil and Arm-R-Seal on all but the 2x12. It had the same but was sanded flat and then 6 coats of nitro laquer was sprayed on - all except the front piece. Hey don't laugh - its a 'prototype'