For easy comparison of many energy provider rates with controls for Gas / Electricity usage estimate and the duration you're planning on keeping the tariff for.
Note that the rates are hardcoded in a CSV file so they're probably not up to date, may contain mistakes and are only valid for my location.
I've represented annual discounts like OVO's 60 pound discount for only having online and app customer support by including the discount in the daily standing charge.
Go here to see it: http://iamscottmoyers.github.io/energy/
Or to get the code and run it yourself:
git clone https://github.com/iamscottmoyers/energy.git
cd energy
python -m SimpleHTTPServer 8000 &
Then point your browser at localhost:8000