A rather brief post but this are some quick ones for you:
First Great Western also operates the Night Rivera, with 4 57/6s and Mk3s,
Arriva Trains Wales operates the WAG Express, now operated with 67s instead of 57/3s and Mk2s - standard - and a Mk3 RFM.
Scotrail i think, still has a daily Fife Circle diagram, as well as the Caladonian Sleeper - Class 90 hauled from London Euston to Edinburgh / Glasgow, Class 67 Worked to Fort William, Inverness & Aberdeen.
Greater Anglia - Most Norwich to Liverpool street Express services are Class 90 & DVT worked, as well as the occasional Norwich loco hauled diagram - usually top and tail 47s with 2Mk3s and a DVT.
Virgin Trains - Pretendolino - Hired Class 90 from Freightliner, with reliveried VT Mk3s & DVT, as used on London Euston to Birmingham New Street services - as needed, and a Fridays only to Crewe.
And then theres the Chiltern Mainline sets - ex Wrexham & Shropshire -running between Birmingham Moor Street & London Marylebone, and the 'Scratchpot' set used on a morning and evening peak Banbury to Marylebone services.