One current project is to make a Lego telephone.

Here's the preliminary work...

Parts:

1 RadioShack Apollo Fashion Phone (43-868), any color, $20
2x 400 piece buckets of Lego bricks (2494), $5.99 ea
1 Lego base work sheet (unknown serial #), $5.99
2x Lego 9v connector plates (5037), $??
14x subminiature pc mount switches All Electronics, FSM-5 or FSM-6, $.25 ea
26 gauge or any light wire - I bought 5 feet of ribbon cable for $2.50

2 tubes gel-style cyanoacrolate


Tools:
Dremel moto tool and various bits
X-Acto knife and blades
Soldering iron
Wire strippers
Cordless drill and various bits.

Disassemble your phone completely. You'll need to break some plastic struts to do this--no going back!

Cut two 10x16 panels from the Lego work sheet. Be careful not to do this to yourself.

Assemble a 3 brick high shell out of single width bricks with room for the modular jack (2 pips wide by two bricks high), glue together with C.A. gel. Sand off all the pips on the top with the Dremel tool since the base doesn't have mating fixtures for pips.

Lay out the control panel.

Solder the microphone, removed from the phone, to a 2x2 connector plate (cut from larger stock) and glue to a hollowed out 2x2 brick with sound holes drilled in the top. To hollow out a 2x2 brick, I used a very sharp forstner bit to cut away the post. Do not even think about trying this with anything but a cordless drill, and even then be careful because the drill may bind on the post and rip the brick out of your fingers. A small vise is probably best to hold the brick.

Glue together two 2x4 bricks and hollow them out. Drill holes in the top for sound. Grind down the sides of the telephone speaked and embed in the brick. Solder a 2x2 connector plate to the speaker, and glue to the back.

Prepare 14 Lego brick switches. To do this, splay the pins of the switches, remove the plastic from the top of two diagonal corner pips (to expose the metal contact fully), and solder in place. Test the contacts with a volt meter and trim off legs and blobby solder. Cut off the bottom third of 14 2x2 bricks, remove the center posts, drill holes for the switch stems and sand down the pips so the switch clears. Make sure to cut a small dent in the top of the brick where you want the hole, otherwise the drill will decide for you. Finally, glue the plates with the switch to the tops.