At plone conference I saw Andy McKay demonstrate his Clouseau product, but I have only just got round to trying it. Incredibly useful - I particularly like the way you can use it in context, i.e. when editing a plone page you can click the magnifying glass icon, type "context." and instantly get a list of the attributes and methods available via the Schema. For people like me who find the zodb a dark and mysterious place, this is a nice environment to use to explore. Cheers Andy!