Major Roman numerals
History   Wikipedia  
 Mnemonic:
50, 100, 500, 1000
Lovely Cadbury Dairy Milk (L, C, D, M).

 Mnemonic:
50, 100, 500, 1000
Lazy Cats Don't Move (L, C, D, M).

 Mnemonic:
1, 5, 10, 50, 100, 500, 1000
Insane Villagers X-rayed Lint Concerned Dave Many-times (I, V, X, L, C, D, M).