do you want to borrow my idea? this will work, get some bread board and make a little radio transmitter, they sell well enough on ebay and are cheap and easy to make, get enough bits from broken electronics and a schematic from tinternet.
radio snoopers are really simple ass circuits and they are kind of fun little toys to buy and play with, think of them as snacks when you sell them to people.
I know a girl who makes little headress/diedem things with flowers on, shes studying physics but manages to still make 1k a week selling these little things on ebay, they look quite good but the point is people will buy them.
you can stick a little radio snooper in anything too so remember not to kill half of your market by making it geek only, girls love spy crap as much as boys too, just shove one in someting you could sell on etsy, its quirky enough to be popular straight away (think of a title on a basic looking alice band on etsy, spy on your boyfriend, just leave this hairband in his room and hang outside)
make and sell is the oldesst and most successful business model fredbill, nothing makes money like doing some sort of actual work
(that or get a kitchen job, they will rip you off but illegaly employ you :| )