- A MAYBE tag on a statement creates a choice point, containing the entire state of the program except ABSTAIN/REINSTATE status, after which the statement is performed normally.
- A GO BACK statement backtracks to the most recent choice point, redoing the statement in the negated sense, ignoring it if it is active and performing it if it is abstained from.
- A GO AHEAD statement eliminates the most recent choice point from the stack.
- Threaded INTERCAL
- Backtracking INTERCAL was implemented in version 0.25 of C-INTERCAL.