Business/Investment Ideas?

So long story short, I was left around £7,000 for my 18 birthday. It was left because of the loss of my dad, and I really want to do something with it that would make him and my family proud. I also don't want to just spend it and have nothing to show for it.
So I want to invest or possibly start up my own business. I know how hard and costly it is and realistically £7,000 could disappear quickly. So obviously I'm looking for a small business idea or investment idea.