Hi,
I just found an Ebay item, that is pretty amazing and simple
to build, if you want to follow the sun throughout the day to
amplify the sunlight:
http://cgi.ebay.de/ws/eBayISAPI.dll?ViewItem&item=6066287018 (http://partners.webmasterplan.com/click.asp?ref=284148&site=1382&subid=&type=text&tnb=32&diurl=http%3A%2F%2Fadfarm.mediaplex.com%2Fad%2Fck%2F707-3922-3266-17%3Fmpro%3Dhttp%253A%252F%252Fcgi.ebay.de%252Fws%252FeBayISAPI.dll%253FViewItem%2526item%253D6066287018)