I've never thought of colanders as having much room to differ from one another; it would be hard to find one that doesn't do its job properly, and they all look fairly the same. Despite the fact that colanders aren't exactly sophisticated kitchen tools, Joseph Joseph manages to inject both savvy functionality and aesthetic sensibility into theirs. Then again, if any gadget company can do that with a mundane tool, it's definitely these guys.
The Folding Colander ($19.95 from amazon.com) starts with a food-safe polypropylene material that allows for its unique construction: The flat, irregular octagon folds up into a square, yielding four corners that won't crack or weaken with constant use and reuse. Folding it is intuitive, and arrows clarify for first-time users, but a not-so-obvious feature I enjoyed was how the shape locks into place for sturdy straining. Very smart.
But why a folding colander? What's the point? Well, storage space is key—and from reading your constant comments, it seems that it's equally a concern outside of my cramped Manhattan kitchen. Beyond that, though, I found that the folding really helps for efficiency. For instance, if you're chopping veggies for a salad, you can use the flat colander like a cutting board before folding it up and collecting your goods for a quick rinse. Given that you chop in the center, it actually works.
Other advantages revealed themselves to me pretty quickly. Cleanup, for one, is made easier by the slightly larger holes. (I can't stand cleaning my wire colander, even if I've only used it for pasta. Things always get stuck in the teeny holes.) I do think that the size can be somewhat limiting though, if you're talking about that same big pot of pasta—this colander is a little smaller than your average round one.
Should you run out and spend the extra $10 on a fancy colander if you already have one? No, there'd be no point. This colander doesn't do anything your old one doesn't. But if yours needs replacing, it's worth considering—durability and convenience might well make it worth the price if you're already searching.