A special class are the “double true” alphametics. THese are the puzzles I want to have a look at in this post.
1) I listed one before:
THREE
FIVE
FIVE
SEVEN
TEN
——+
THIRTY

The university of Bieleveldt has a nice list:
2) SEVEN + SEVEN + SIX = TWENTY difficulty: 2
3) EIGHT + EIGHT + TWO + ONE + ONE = TWENTY difficulty: 3
4) ELEVEN + NINE + FIVE + FIVE = THIRTY
5) NINE + SEVEN + SEVEN + SEVEN = THIRTY
6) TEN + SEVEN + SEVEN + SEVEN + FOUR + FOUR + ONE = FORTY
7) FOURTEEN + TEN + TEN + SEVEN = FORTYONE
8) NINETEEN + THIRTEEN + THREE + TWO + TWO + ONE + ONE + ONE = FORTYTWO
9) FORTY + TEN + TEN = SIXTY

This list is, however, not exhaustive. Here are a couple more:
10) THREE + THREE + TWO + TWO + ONE = ELEVEN difficulty: 3
11) ELEVEN + THREE + THREE + THREE = TWENTY difficulty: 4
12) ELEVEN + THREE + THREE + ONE + ONE + ONE = TWENTY difficulty: 4
13) SEVEN + THREE + THREE + TWO + TWO + ONE + ONE + ONE = TWENTY difficulty: 4
14) SEVEN + FIVE + TWO + TWO + ONE + ONE + ONE + ONE = TWENTY difficulty: 3
15) SEVEN + FIVE + TWO + TWO + TWO + ONE + ONE = TWENTY difficulty: 3

I feel there are a couple more lurking out there, but I hope to list more of them in a future post.

They exist in many languages, about a year ago I published some Dutch ones. 

New puzzles are published at least once a month on Fridays. You are welcome to remark on the difficulty level of the puzzles, discuss alternate solutions, and so on. Puzzles are rated on a scale of 1 to 5 stars. You can check your solutions here.