The ever popular Crown Royal bag. It's become a trope, a staple of gamers as the dice bag to own. In the beginning it was cool for a kid gamer to have a quality bag made by a liquor company. It said you were dangerous, beyond your years, or that your parents drink too much. Ask around the table and people will tell you that this is the bag to own.
Bantha Pudu!
You can lead or you can follow. Traditions are made to be broken and you are your own man/ woman, and you know you don't need to spend your life as a cliche. Besides, the ever popular dice bag just isn't all that functional.
- Even when the drawstrings are closed, there is a gap that a die could pop through. So people fold over the top. The also wind the drawstrings around and around because to tie and untie them is madness. Even so, there's no guarantee it won't unravel and open in your pack, spilling dice everywhere. So much work for a cliché.
- A bag is an amorphous blob. Your pack is filled with flat, nicely stacking objects and then your dice get thrown in and eat up more room than they should or prevent other things from stacking nicely. Bleh.
Zippers!
Get a pencil bag with a zipper enclosure from the school supplies department or an art store. Your dice won't fall out. It's the 21st Century folks! Use 'dem zippers! Magnetic enclosures might also work unless you have metal dice. It might sound cool to use a magnetic to store your metal dice, but you may find it hard to roll them if they get magnetized.
BTW this is what I currently use for my jumbo dice. It also holds pencils. Who knew?
Altoid Tins!
Yes the amazing Altoid company's tins will actually hold 2 x 7-die sets of standard dice and they are fairly good at staying closed. Plus you now have a nice tidy square for backpack or pocket storage. You can even paint the tin to make it more custom (although you might have to shellac it on at first to get rid of the raised lettering.
Other
I've also used zippered cel phone cases, hard glasses cases, a lot of things. Look around, get creative. Just remember, keep it small. Your dice should be handy, not a burden.