Nice ideas. What made you choose the standby symbol?
I chose it for two reasons. One, it is associated by people with "power on" and I think SFML "turns the power on." Two, it's actually tech/computer related (I kept thinking of a lawn company looking at the green pentagon... it's not bad, but I wanted to try and get people to actually think of something computer related). I originally thought of the block one because I was trying to create a distinguishable symbol (the generic round standby symbol is used outside of SFML). I decided to merge the two ideas (the pentagon, representing the 5 parts of SFML, and the power symbol) and that's how I came up with that version.
Here are some different versions (the glowing ones were supposed to emphasize "power on"):
And Laurent, here are a few with the "SFML" by it:
Again, just rough sketches. I can provide the SVG file if someone wants to play around with it or try different font combinations. I can also post more font combos myself if anyone would like me to.
Here are a few colored options:
Again, I just want to emphasize these are rough sketches.