Hmm... excellent question. How about a device that allowed me to travel in and out of any book, film, TV 表示する または video game at will? Or... a portal that allowed me to travel between worlds? My brain is a bit cheese-like at the moment, so I'll probably come up with some better ideas later and 編集 them into this answer.
Hooo I like your idea about the elixer :D Foooood<3 anyway ;3 I would invent a ヘルメット to help me get the 本 written material into my head, in a short time, so I will not waste time learning for exams :DDD And of course I will be installing a button to 削除 non-essential information in order to not overload my brain :}
Or, in a different thinking direction, make up a 線, レイ reduces the calories of 食 to 0, so the 食 will be the same thing! only he could not make us fat, then we can eat as much as we want!!! :D That's about what I'm doing now ... But would not hurt to invent something like that ^0^
A way to clone myself but to also morph back togehther with the clones, so we could learn a bunch of information at once bt morph together to remember it xD Oh and something that can make あなた shapeshift... and this thing that would let me imagine a picture and create it without actually drawing it out, that way, my art would look good and I wouldn't have to draw xD
What would I create? That's a toughy, but if i had to create one invention, i'd probably create a lazer that can give us fanguins もっと見る power so that we can all take over the planet.