Very excited to discover the Rasa takeout, located at 5 Rathbone street (near Tottenham Court Road and Oxford Circus) has nice, filling takeout lunch boxes with rice, a chapathi, two side dishes (a curry and a daal), a side savory and a dessert cup, all for £3.50. Stunning! They had something that cost even less, I think £2.50, but I'm not sure what was in it. There were two meat options today (chicken curry and/or biryani, I got the biryani and got a free coconut-based veg curry as one of my two sides) and there was, and probably always is, a all-veg options.
The restaurant also has a full service side on the other side of the building, but why bother if you're in a rush and looking for lunch? Rasa Samudra, I am a convert!