This a modification of meenzal's Fireflies in a Jar instructuble which I thought was really awesome. I made a few as presents for friends and family and then wanted to try something a bit different. The plan was to cut the bottom off of a clear glass wine bottle, make a nice wood base for it and then build the electronics as previously described. While there are lots of Instructables on cutting a glass bottle I took the easy way out and used a tile saw. The base was turned by my buddy Slittape on his wood lathe out of some scrap decking mahogany and finished with Butcher's wax.

What you'll need:

a clear glass wine bottle
a 5" by 5" piece of hardwood scrap for the base
2 IN4006 diodes
10 0.47 uF film capacitors
10 3.3 Mohm 1/4 watt resistors
10 NE-2B neon lights
16 gauge bare copper wire
power cord with inline switch

Tools:

tile saw
woodworking lathe and cutting tools
sandpaper, various grits
drill press and Forsner bits
soldering iron and solder
hot glue gun and glue sticks
wire cutters

Safety note: This device works at US wall voltages and therefore extreme care should be taken once the power has been connected. Note that capacitors will store a charge and should be discharged safely after being powered up.

Step 1: Cut the Wine Bottle

Drink the wine. Replace the cork in the bottle. I wrapped the base of the bottle with a band of masking tape to support the glass while cutting and reduce the amount of chipping etc. The cut itself was very quick and left a fairly nice finish. Since the cut end will be embedded in silicon caulk I didn't bother to try to get it smooth.

Step 2: Make the Base

Fortunately my buddy Slittape has a woodworking lathe and is an excellent wood worker. After some discussion he used a scrap piece of mahogany decking and turned it to about 5" diameter. He then rounded off the edge. We measured the diameter of the cut off wine bottle and cut a groove in the top surface to match. Lastly he used his drill press to cut a hole for the power line to enter from the side and out the top. I then smoothed it all down with sand paper and finished it with two coats of Butcher's wax. As you can see it came out quite nicely.

Step 3: Build the Electronics

I followed the original Instructable almost to the letter here with the following exceptions:
I used slightly different values for the capacitors and resistors, however the product of the capacitance and the resistance are roughly the same as in the original.
I did not use any shrink tubing as I didn't think it added anything to the set up.
It wasn't necessary to cut the bottle for the power cord as the base had built in routing for the power cord.
I used a power cord with an inline switch.

Step 4: Assemble the Bottle

Once the electronics are connected and working satisfactorily all that remains is to secure the bottle in place. i used a bead of silicon caulk about half filling the groove cut into the base. Setting the bottle in place caused the caulk to ooze up both sides of the bottle leading to a secure attachment. Remember that this is a mostly irreversible step so make sure everything is right first.
Flip the switch and enjoy your fireflies.