I have a serious "hobby" (read: addiction) concerning cheap ebay gadgets and thus, I own countless small silly items that get little or no use. As an Avid DIY guy however, more often than not, I end up using the item or part of it later for something else. My Gorillapod knock-off will NOT sustain my 5D3, but it has become my favorite portable microphone stand for my home studio and/or when I perform my electronic singer/songwriter/laptop music:)
I am still undecided on the white balance lens caps I own - they could be really useful for DSLR video when I get around to tweaking the wb bias settings (the caps I have typically result in a cooler wb than I like)
I can only agree on the horribly designed lens
hoods.. Bought a screw-in version by mistake for my 35mm IS - I barely needed to mount it to realize that it is a waste of good plastic
Even though the remote shutter release seems like such a usable item it barely gets any use whatsoever.