I don't know that I have any particular mess to share with you, though I did find a pretty amazing product recently. I am one of those people who for the past eleven years has just lived with the fact that the caulking around my tub was going to be gross and disgusting, ranging in color from orange to black. I struck gold though, I asked some friends what they use.
One of them told me that they used Lysol's Mold and Mildew. It's purple and it has bleach in it. I went to my grocery store and looked for it, no luck. BUT there was a Tilex product there with the same description Mold and Mildew with bleach. I bought it. I took it home, sprayed it in my bathroom and walked away for the recommended 5 minutes. I came back expecting to see what I saw when I left, but no, it was white! I still have some that is persisting, but honestly I think that the caulking may need to be replaced. It is absolutely amazing how well this stuff worked, especially considering I didn't have to do anything except spray it on. It's also getting the orange grout clean. I feel so pleased with this product. Amazing stuff.
So what do you do for the crude in the caulking?