I met a woman who wrote an ap for her smart phone that catalogues photos of all her fabrics by color family, type, and pattern, along with running total of yardage. It was impressive, specially since she mostly collects reproduction prints, many of which come in various color ways and it's easy to re-buy. Since it's on her phone, she has it handy while shopping, but can also keep the list on her computer for online purchase consultation.
I personally don't buy or organize that way, but I think it's a great use of technology, specially if you are just now starting to collect fabric.