See 31 ... ♖e2xc2! in the following playchess.com blitz game as a great example of this tactical idea.

Position after 31 ... ♖e2xc2!:

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Black sacrifices his all-powerful 7th-rank e2-rook for the measly White c2-pawn. Why? Because eliminating the White c2-pawn frees his connected advanced c- and d-pawns, transforming them into connected passed pawns on the 6th rank, which easily defeat the hapless White rook.

Event "3m + 0s, rated"
Site "?"
Date "2006.08.23"
Round "?"
White "Varvarka_87"
Black "Ivanisevic Ivan"
Result "0-1"
WhiteElo "2665"
BlackElo "2904"
ECO "B30"
PlyCount "64"
EventDate "2006.08.23"
EventType "blitz"

Ducats=0+- 5
1. e4
%emt 0:00:00
1... c5
%emt 0:00:00
2. Nc3
%emt 0:00:01
2... e6
%emt 0:00:00
3. Nf3
%emt 0:00:01
3... Nc6
%emt 0:00:00
4. Bb5
%emt 0:00:00
4... Nd4
%emt 0:00:00
5. Bc4
%emt 0:00:01
5... Nf6
%emt 0:00:04
6. O-O
%emt 0:00:05
6... a6
%emt 0:00:02
7. e5
%emt 0:00:09
7... d5
%emt 0:00:02
8. exf6
%emt 0:00:01
8... dxc4
%emt 0:00:01
9. fxg7
%emt 0:00:00
9... Bxg7
%emt 0:00:00
10. d3
%emt 0:00:00
10... b5
%emt 0:00:07
11. Bg5
%emt 0:00:25
11... Qc7
%emt 0:00:11
12. Nxd4
%emt 0:00:10
12... cxd4
%emt 0:00:02
13. Ne4
%emt 0:00:00
13... Bb7
%emt 0:00:03
14. Qf3
%emt 0:00:29
14... Rg8
%emt 0:00:03
15. Bh4
%emt 0:00:09
15... Be5
%emt 0:00:09
16. Bg3
%emt 0:00:10
16... O-O-O
%emt 0:00:01
17. Bxe5
%emt 0:00:03
17... Qxe5
%emt 0:00:01
18. Qxf7
%emt 0:00:00
18... Bxe4
%emt 0:00:07
19. dxe4
%emt 0:00:00
19... Qxe4
%emt 0:00:02
20. f3
%emt 0:00:01
20... Qe3+
%emt 0:00:02
21. Kh1
%emt 0:00:01
21... Qg5
%emt 0:00:37
22. Qxe6+
%emt 0:00:05
22... Kb7
%emt 0:00:03
23. Rg1
%emt 0:00:00
23... Rge8
%emt 0:00:02
24. Qh3
%emt 0:00:04
24... Re7
%emt 0:00:01
25. Rae1
%emt 0:00:03
25... Rde8
%emt 0:00:01
26. Rxe7+
%emt 0:00:01
26... Rxe7
%emt 0:00:00
27. b3
%emt 0:00:01
27... c3
%emt 0:00:02
28. Qg3
%emt 0:00:05
28... Qxg3
%emt 0:00:04
29. hxg3
%emt 0:00:00
29... Re2
%emt 0:00:00
30. Rc1
%emt 0:00:03
30... b4
%emt 0:00:01
31. Kg1
%emt 0:00:01
31... Rxc2
%emt 0:00:03
32. Rxc2
%emt 0:00:02
32... d3
Time (Lag: Av=1.56s, max=2.6s) . %emt 0:00:01 0-1