[astrange]

Alpha-GPC is just choline, so you can get it by eating eggs. Amino acids and mushrooms are also quite accessible.

Modafinil is straight up better than caffeine though, which is a crappy and addictive stimulant.

[drilbo]

"just" choline is a little reductionist, it's much more bioavailable.

I'm not sure where the distinction actually lies, but it is also considered a (generally recognized as safe) drug.