I just want to start by saying I absolutely love this question!
Note that you did not specify a monetary range, so I have provided suggestions that span the gamut.
Are you talking about adults only, or including children in your target help group?
For minors, setting up a UTMA/UGMA and buying them an investment can work, provided you're willing to use it as a tool to help them learn about saving and investing for the long term. If you're not close enough to get a full fledged investing account opened, there are services like stockpile.com that let you do it easily. This allows you to give money that isn't touchable until they've learned good habits and/or it's really needed (college age).
Another option is matching of some form.
For younger kids, consider matching a 429 account, to help them go to college. Or for teens consider matching funds for their first car. - Per Tracy Cramer's comment
For college students, offering to help pay for school by matching any cash money (not loans) they can put up at the time will encourage a strong work ethic. I would couple this with a requirement of a certain GPA, so they don't just let the schoolwork suffer in order to work. As a bonus, this makes post-school full-time work seem like a vacation.
You could also match earnings for someone who has a poor work ethic and difficulty keeping jobs. This provides an incentive for them to maintain financial stability, especially if they're having trouble finding good paying jobs and feel like their earnings are insufficient for the amount of work the jobs they can get provide. This would need a structured tapering system so that them earning more money doesn't mean an equal reduction in your help; otherwise there is no incentive to professionally grow.
You could match 401k / IRA investing to encourage saving for retirement. Even if they learn nothing, you may save them from poverty in old age when it's too late for them to do much about it.
Something They Can Use
Consider focusing on something that they can and will really use; buy them potential instead of a physical item.
For instance, a hard worker supporting a growing family can often hardly afford a used $50 P&S camera. If they love capturing memories with their kids buy them a nice dSLR that suits their needs; You're buying memories instead of buying a thing.
Know someone who always wanted to raise chickens for 'home-made' eggs? Maybe you can buy them the coop and chickens? Give them the potential to do something valuable that they couldn't otherwise afford the initial investment for.
Know someone with a large family that supports themselves well enough, but doesn't have a whole lot of 'extras'? How about buying them a pool, or a membership to a private pool?
You can avoid the money being wasted by giving them the kind of thing they might waste the money on. :)
If you know someone who works hard and is just managing to support their family, it could help quite a bit to send them on an all-expenses-paid vacation. Long-term stress can have serious health effects (physical and mental) that you could help alleviate.
Paying for an extravagant holiday dinner for those who couldn't afford it would be helpful in a similar way.
This section works especially well for elders in your life. Know someone who is retired and did well, but dreamed their whole life of owning a Corvette that they could just never attain? Buy them a two year old Corvette. You're not teaching anything or supporting good habits, but they may not need that. Maybe they spent all their money on their kids, or helping others...give them a reward.