Conway's Hello World
My first attempt to this, a relatively simple solution. It fires a couple of glider barrels. Each pair of gliders turns into a block, which then form the text. This process takes about 16000 generations (you can set a frame skip or use the superstep button in my simulator).

Direct Link. Move around with right mouse, zoom with mouse wheel.

Link to .rle file (also works with Golly)

Image of the pattern 32:1: