No, it's not what you're thinking with your dirty mind! The 'S' and the 'M' in the S&M Cafe stand for sausages and mash – which are their specialities.
The set up is your traditional caff but better, meaning the table cloths are still laminated, but as well as your traditional London sausage you can also get wild boar and apple, apple and cider, Caerphilly cheese and leek and mushroom and tarragon sausages. Accompanied by a selection of different mashes as well. What's really good about them is the you can build your own sausage-y combo meal, and have a selection of different sausage varieties. It's £7.95 for two sausages, mash and gravy and £8.95 for three sausages, mash and gravy. They'll also occasionally do a seasonal sausage or two.
While the sausages are a staple across the cafes – Islington, Spitalfields, Greenwich, Ladbroke Grove- the rest of the menu varies, with some venues, Spitalfields and Islington, serving a larger selection of mains, and some of them serving more limited menus.
Obviously if you're a real traditional Londoner you might want to drink tea with your sausages. But you can also have wine or beer if that's more appropriate for the time of day you're upping your sausage content.
As well as the main, meaty menu, they also do Breakfast and Brunch, which as you might have guessed, is heavy on the bacon side of things. They also do tempting pies.
This is best of british all right, but the food is better than the greasy spoons they're based on, and they're cheaper than a gastro pub.