Tonya runs into the room "You're far too big!" she cries (you must be at least 30 feet tall) "shrink back to normal size before any side effects happen!"
You concentrate hard on getting smaller, screwing up your face and shutting your eyes tight - but when you open then, you see that you're still the same size!
"What happened?" you ask "I can grow bigger at will, can't I?". You think and grow another 2 feet.
"DON'T GET ANY BIGGER!!" yells Tonya "It seems you can only grow yourself bigger because that what the machine was doing at the time of breakdown."
"Can you do anything?" you say.
"We don't know." replies Tonya "If you don't get much bigger we might be able to devoloup some nanobite technology within a month. In the meantime, you'd better learn to control your thoughts. There's no telling how big you'll grow!"