what to do with leftover roast lamb?

I don't know why, because I've never used lamb in this way, but when I read your question, i thought of empanadas.

1) cut into large cubes, stick a toothpick in it, and serve as an appetizer along with Tzisiki (sorry about the spelling...)
2) take a wrap, add some lettuce, tomato, red pepper and onion, throw on strips of lamb, add Tziski and wrap (okay, almost a sandwich)

Cut it into cubes and stir it into a thick sauce made with onion, garlic, diced canned tomato, spinach, oregano, and cinnamon. Serve over orzo, and sprinkle with feta and chopped kalamata olives!

It is snowing and we have freezing rain here in Seattle. Unusual weather for us. So when I read your question my first thought was "Send it to me!"

I've made variations of this salad with leftover lamb - leg, shoulder, any roast: http://www.nigella.com/recipes/view/anglo-asian-lamb-salad-39 A little sesame oil is good in the dressing too, any kind of greens, and a lime wedge to squeeze on top.

If you have some rare meat, cut it in chunks and make aargersi's lamb and sweet potato stew - I swear by it.

http://www.food52.com/recipes/14943_lamb_and_sweet_potato_stew

Make a salad of sorts with red onion, artichokes hearts, tomatoes, cucumbers, black olives, red wine vinegar and/or lemon juice and some olive oil, parsley, salt and pepper. Warm up a pita. Wrap some lamb, some plain Greggk yogurt, and the salad up in the pita...I know you said beyond sandwiches, but this is really my favorite leftover lamb recipe.

My brain is working overtime here, mrsL! Fry up some thin eggplant slices until nice and crisp. Slice the lamb and cut the slices to fit the eggplant pieces. Top with some Fontina Val d'Aosta cheese (or other flavorful semi-soft cheese to your taste) and broil until the cheese is browned and bubbling. (Buon Apetito!) ;)

oh, great ideas! thank you!!

Midge, never heard of HP sauce - will have to look for that.

gonna go make a sandwich now - i'm hungry.

Lamb and cabbage or spinach stew with tomato, onion, garlic ,paprika

Sandwiches! Roast lamb, soft cheese (like brei), and some sort of sweet heat. I really like the blackberry-serano jam at Whole Foods.

Lamb hash, with diced potatoes and onions. Delicious with HP sauce!

Make shepherd's pie! I always aspire to do this the next time I make roast lamb, after years it still hasn't happened. Hope you try it! http://www.channel4.com/4food/recipes/chefs/hugh-fearnley-whittingstall/hugh-s-mum-s-shepherd-s-pie-recipe