Risk of changing clocktime on MySQL server host I have a MySQL server host that have a clock that is about 75 minutes wrong. Is there any risk in changing the hosts clock while MySQL is running?

Update: Obviously NOW() and other functions returning current time will return a different result. In my case I am thinking of spinlocks and other scary internals in MySQL.
Binary logs will record the events sequentially with whatever timestamp it has. Using any binary log around the time of a clock change makes the particular log unusable for PITR (Point-in-Time Recovery).
If the DB Server is a Slave, Replication may skip processing certain events.
If you have Binary Logging or Replication Enabled, I would do  the following

On DB1, stop writes to the database
On DB2, run SHOW SLAVE STATUS\G multiple times to make sure there are no new commands being processed and Seconds_Behind_Master is 0
On DB2, STOP SLAVE;
On DB1, RESET MASTER; (Erases all binlogs)
Stop MySQL Shutdown on DB1
Stop MySQL Shutdown on DB2
Set the Linux Time on DB1 and DB2 (Make sure times match)
Start MySQL Shutdown on DB2
Start MySQL Shutdown on DB1
On DB1, RESET MASTER; (Erases all binlogs again)
On DB2, CHANGE MASTER TO MASTER_LOG_FILE='mysql-bin.000001',MASTER_LOG_POS=4;
On DB2, START SLAVE;

The idea here is to make sure all binary logs and relay logs are time synchronized. The NOW() function could then be correctly interpreted from these logs.
CAVEAT
Be very careful about changing clock times when it may not be necessary when it comes to Daylight Saving Time. Since the clock time is written in binary logs in seconds since Jan 1, 1970, it may not be necessary. Since the clock is 75 minutes off, do this ASAP. Don't wait until DST kicks in.