We have an "income protection plan", which in essence pays out 75% of your salary until your official retirement age (65 in our case).
The major drawback is that under the scheme you aren't allowed to earn another salary, if you do the monthly payout will be reduced accordingly.
Personally I'd prefer a "three times the salary" lump sum or similar, but there are very few UK employers who do this.
As Chilli says, Traffords offer the option, but for me, it's not far off £1300 per annum for a £35K payout.