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IcoMoon, the wonderful service for creating icon sets for production use, just released some upgrades to their SVG sprite output that does a great job. The new Quick Usage feature uploads the SVG sprite and required assets to some ready-to-use hosting and gives you copy and paste code to get started. Or, click the View on CodePen button to move the party over to CodePen to play.
See how it works:
I like how their new embedder script works. The best bet for cross-browser
<use> support is to embed the SVG you are using from right in the document. But that doesn't cache as well as referencing it as an asset would. So the best bet is just to ajax for it and drop it in the document. That way it can both be cached and give you the best support possible.