Last May I found a really cute copper wire and marble ornament in an Idaho geocache, and it hung from the rearview mirror for the rest of our trip. It was simple, just wire twisted into a heart, one end coiled around a marble.
First, the materials and tools. Marbles, of course. For wire, I wouldn't use anything finer than 20 gauge; 18 or 16 gauge would be more robust, but harder to work with. You will also need jewelry-making pliers (these have smooth jaws, so they won't mark the wire). I used chain-nose, flat-nose, needle-nose, and nylon jaw (for hardening the wire). You might also want a file to smooth off the cut ends, especially on the hook.
I'd planned to use the copper dangle as a sample, but in truth, I found it impossible to duplicate it. When I started to twist a length of wire using my jewelry making pliers, the wire took on a mind of its own. On the first few I played around with different twists and flat spirals, following the wire where it led, being flexible with the design, adding wire links to hold things together if necessary. When I was happy with the result, I used the wire hardeners to set the wire.
I like silver and brass wire best, but also made them from colored craft wire like red, purple, dark green, and navy blue.
Once I'd made a few simple dangles with marbles, I tried adding a few crystal beads. If you thread them onto the wire, add a tiny twist to the wire above and below to hold the bead in place. Or you can wire beads to loops so they dangle.
Instead of a marble, try using a large faceted crystal bead. They look spectacular wrapped in wire and held between the sides of the ornament. My first attempt was a bit rough, but I really like the idea and will try this again.
Craft wire is inexpensive, perfect for playing with. Once you work out your favorite designs, you can always switch to more expensive silver or copper wire.
Don't be afraid to experiment... you might just like what comes from it. One of my wire hearts came out too short, so instead of dumping it and starting over, I figured out a different design, which has two wings: one wrapped around a marble, the other with bead dangles to balance the weight. I love how it spins around the hook and catches the light.