Tell us about yourself!
Old post but I shall offer my findings anyway. I happened to have made an awfully similar design by coincidence. I can assure you it works. Only really useful for small spaces, this one in particular is for our shower room which has poor ventilation but it keeps the condensation away. I chose a £1 storage draw as a case because the top draw houses the fan and 5v amp USB lead (power) whilst the lower draw of course houses the silica.I am working on a slightly improved design whereby the silica is epoxied (carefully) on to plastic fins which line the tray thereby increasing the silica surface area.