If you're lucky enough to have an outdoor space to call your own, check out this days-of-the-caveman-inspired lighting source. Solar Rock Spotlights are rechargeable and solar-powered, so both the earth and your electric bill will thank you for choosing this option.
Properly positioned, we think these could be plenty of light for an ambient glow on a patio in the city, especially surrounded by a small garden of potted plants that allow the rocks to blend in a bit--and give the lights something to highlight.
The LED light contained within the rock is controlled by a sensor that only turns it on when it's dark out, and off when it's light out.
The retail price of $49.99 nets you 3 Solar Rocks.