Plusnet is what I have for my own mother's connection, which I took out when they still listed their low usage 10GB package at 5.99 a month. It's crept up over the years to 7.99, but for the few emails she sends, that's adequate.
However, since they're a BT-owned company, and not quite as small as they once were, they probably don't fall into the 'boutique' category anymore. But I suppose that's as good a way as any to illustrate that while these more customised outfits may be ideal for reg readers, if you just want a basic connection, sometimes using one of the big outfits may be a better choice.
Biting the hand that feeds IT
