In MySQL you can set a session variable called time_zone to change the timezone. This is useful e.g. when looking at timestamps from another country. Here is an example:

mysql> select now();
+---------------------+
| now()               |
+---------------------+
| 2010-12-30 18:59:18 |
+---------------------+
1 row in set (0.00 sec)

mysql> set time_zone='Brazil/East';
Query OK, 0 rows affected (0.00 sec)

mysql> select now();
+---------------------+
| now()               |
+---------------------+
| 2010-12-30 09:59:29 |
+---------------------+
1 row in set (0.00 sec)

Is it possible to put that in an option file e.g. .my.cnf ?

When I try, it doesn't work. All I get is:

mysql: unknown variable 'time_zone=Brazil/East'
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