What's the recommended way to store current time using PHP and MySQL?

My initial approach was:

$current = time(); // save this to column CURRENT_TIME with column type VARCHAR

//retrieve it like this
$retrieved = mysql_query(....) //assume query for getting the stored time value
$time = strtotime($retrieved);

I have come across the following approaches:

1. use gmstrftime to handle gmt
2. use INT instead of VARCHAR for the column
3. use the mysql function CURTIME or CURDATE
4. use the UNIX_TIMESTAMP mysql function

none of which were using the DATETIME or TIMESTAMP mysql var type.

Do you have a better approach for this one?