I have a Project (such as "Weddings" or "Gigs" or "Holidays" etc), and within those are Albums for each shoot. The Album is labelled by date and then location/description (ie: 2008-02 Lyn & Clive). This then means I can find my images quickly from that shoot, and they are listed within Projects in date order (year then month).
Obviously beyond that, there is metadata for individual shots or types of shot. However, I can generally remember where things are (even with an archive currently of 50k images), so I don't use search that much.
The other advantage to this is that it's easy to export completed Albums to clients, as things aren't just done by subject matter (which may lead to images being all over the place).