So the one you built will exclude shirts with stripes if "shirts without stripes" is typed directly into a search box? Or there are secondary filters to omit and/or only show certain patterns?
I suppose my ideal UI understands your search, and then moves what it can to (interactively modifiable, as in Amazon's sidebar) filters, keyword searching on the rest.
Currently when I search Amazon and then see that some of my search terms are filter options / categories, I try to remove that from the search (which isn't always easy) in case there's more results I'm missing because they happen not to have the keywords.
