Everyone has problems. But, entrepreneurs can quickly identify which ones are general enough to make a business out of and which ones are too niche. They also see minimum viable products that provide value and don't take a ton of time / effort / money to build.
That brings me something that happened a few weeks ago. I don't recall what I was doing, but I got a text message stating something like, "You just won $1000 gift card to walmart, click-thru to this url (which had walmart in the name) to redeem your prize." I whois looked-up the domain and found that it was owned by some sort of hosting / advertising company and this was clearly some sort of lead-gen scam or worse. I put together a 140 character response and took to my twitter account. I sent tweets of a possible scam to various @walmart accounts and heard nothing. I was so shocked, not because I didn't hear back (though that made me upset), but because I never considered how a company that big would ever manage my message, regardless of how important it was.
I thought about the idea for a while and this past weekend, I started building failrecovery.com. I don't know whether or not this will turn into anything, but that's where my inspiration came from. So my advice to anyone looking for an idea is to become an observer. Keep your eyes open, talk to your friends, co-workers, whoever. Eventually, if you are paying attention and channeling your inner-entrepreneur, and idea will come out of nowhere, like a phishing / link-bait scam.