I actually use the soft Anna bag for packing toilettries for long trips. I use other amenity kit bags for a variety of things:

Hard F Anna boxes: computer leads & weekend toilettry kit
CW MB-branded zip: iPod leads/charger etc. & toilettry kit inflight
KLM J metal box: pencil case & storing various small things (business card, boarding stubs)
Old BA F bag (with old crest): weekend toilettry kit

And others... for various things around the house. I doubt if I would ever pay for these things though, especially at 6.5% of an F ticket.