Fortunately, for those who don't have time for an epic quest, Norse Foundry has an online store!
|Heavy is good. Heavy is reliable.|
But My Table!
Yes, yes, one of the primary advantages to lighter weight, plastic dice is that they don't hurt the table. However, if you want to have your cake and eat it, too (or in this case use your heavy hammers without upsetting your DM), Norse Foundry also provides rolling mats and guards you can use to stop your Dice of Mass Destruction from getting out of hand.
|The Nightmare pattern is ideal for DM use.|
If you prefer your lightweight dice because you enjoy the artsy flick of the wrist, then more power to you. If you'd prefer to stop rolling your dice like an elf, though, go to Norse Foundry's website, and follow them on Twitter while you're at it.