yahoo groups / google groups alternatives???

[justwonderingaimlessly]

I currently run a yahoo group for a community organisation that includes many fairly elderly internet-wary participants. It used to work fine but now yahoo groups have removed the ability to add members directly - you have to invite them or they have to subscribe - and this is defeating a lot of people who want to join. I believe google groups have done the same thing. Can anyone recommend an alternative to yahoo groups and google groups (there is no way I am going to get everyone onto facebook, it really needs to be simple)?

Or a way we could run an e-mail group from our website?

Thanks,