Lots of southern West Coast Main Line stations between London Euston and Wolverton. Specifically, Wembley Central, Harrow and Wealdstone, Bushey, Kings Langley, Apsley, Hemel Hempstead, Berkhamstead, Tring, Cheddington, Leighton Buzzard and Wolverton itself. I know I named pretty much all of them bar Watford Junction, Bletchley and Milton Keynes Central, but I've never known the fast line platforms to ever be used by trains, so they're pretty much useless. Maybe in the past they were used in case of engineering works and such, but I'd be surprised if all these stations has at least one frequent usage on the fast line platforms.