We've got used to tiny returns on the money we save into ISAs, with the best paying just 1.5% interest at the moment.
So the news you can get 10% returns, and access your money you penalty-free, might come as a surprise.
But you can - by using something called an innovative finance ISA - it's just that quite soon you won't be able to open one without passing a quiz first.
And that's not all, how much you can contribute to one of these accounts is being limited too.
Why? Because while returns are a lot higher, the products aren't as simple as some make out.
Laura Suter, personal finance analyst at AJ Bell, said: “From December, anyone wanting to invest in peer-to-peer will now have to pass a test to show they understand the risks they involve, and new investors will be limited to having 10% of their assets in the sector."
And that's not all, providers will also be banned from mass marketing that could see people put money away without seeing the full picture.
How at risk is your cash?
IFISAs take your money and then lend it out directly to people and businesses in the UK.
It's the model banks were built on, just without the banks, and that means you get a rate much closer to the ones offered borrowers - rather than a tiny fraction of it.
This peer-to-peer model means returns of more than 10% are possible, but there are mores risks too.
Firstly, your money isn't protected like it is in a traditional cash ISA - where you get £85,000 worth of cover for each bank you have money in from the Financial Services Compensation Scheme.
Secondly, there's a chance the people you lend to won't pay you back.
So new rules have been brought in by the Financial Conduct Authority, to ensure people know what they're doing before handing over cash.
Christopher Woolard, from the FCA, said: “These changes are about enhancing protection for investors while allowing them to take up innovative investment opportunities. For peer-to-peer to continue to evolve sustainably, it is vital that investors receive the right level of protection.”
Does that mean the party's over for high-returns?
Oddly, an awful lot of innovative finance ISA providers are happy about the new rules.
Rhydian Lewis, chief executive of IFISA provider RateSetter, said: “Rather than a 'clampdown' this is a validation of our mission to open the asset class of loans to everyone, not just the rich."
He added: “No longer can our sector be dismissed as the Wild West of investing: the cowboys are being driven out and the regulation is now on a par with mainstream savings and investment choices.
"We are confident that RateSetter’s growth is set to snowball from here – especially our ISA.”
Yann Murciano, chief executive at BLEND Network, added: "We believe the measures promise to be a positive step forward."
He added: "We already use appropriateness tests, which the FCA is proposing. We believe these measures will have a significant positive impact on the peer-to-peer industry, particularly on the way that loan risks and platform business models are assessed."
