I took my Tamron 17-50mm as my main lens on holiday (as usual) and the first day found that the front of it was damaged - the front ring where the lens cap and hood clip on was loose. It looked like it attached to the rest of the lens with some internal clips and they'd broken on one side. My only course of action if I was to continue using it was to buy some superglue and carefully glue it back in place, which is exacly what I did and it seems to be holding up well. Now that I'm home, if it comes loose again I might get a quote for repair (they can fix the rubber grip while they're at it) but for now I'll leave well alone.
Here are a few shots taken with it in Bergen, Norway.
Bergen by
Jonathan MacDonald, on Flickr
Bergen by
Jonathan MacDonald, on Flickr
Bergen by
Jonathan MacDonald, on Flickr