I love the idea of using used (and washed) red L'Oreal shampoo bottles for ketchup dispensers. Likewise I've tried to turn Dove moisturising shower gel into mayonaise squirty dispensers! Colman's mustard is well catered for by popping it in a yellow fake tan tube.
The only problem is no matter how many times I wash the used cosmetics bottles out their's always a residual taste. I need to find a stronger cleaning solution.