What are the uses for a roasting pan? Do I really need a roasting pan?
I use my roasting pan (either with or without a rack) at least once a week to roast vegetables - either for salads, for sides, or (for instance with pumpkin for soup) to get a slightly different and more concentrated flavour before blending the veges.  I find the vegetables cook more evenly in a roasting pan than a baking pan - perhaps the higher sides help to create a kind of microclimate around the veges??  Not sure about that one.  

When making roast vege salads, you can take the pan straight out of the oven and take advantage of the high sides to mix your other ingredients in (pasta, greens, dressing etc) then serve from there if no one is looking at your serving dish! 

I also use it as a water bath when cooking souffles, puddings etc.