Ted's solution is:

    ' Get the date of the next Friday.
    ' Get today's day number, starting with Saturday = 1,
    ' using the Format$ statement. Subtract the result from
    ' 7 to get the number of days until Friday. Use DateAdd
    ' to add that number of days to today's date.
    MsgBox DateAdd("d", 7 - Format$(Date, "w", vbSaturday), Date)

(With relatively confusing code such as this, the comment describing the solution can be much longer than the solution itself.)

Willy Vanhaelen proposes this solution:

    ' Get the date of the next Friday.
    ' Get today's day number where Saturday = 1.
    ' Subtract from 7. That gives the number of
    ' days between now and the next Friday.
    ' Use DateAdd to add that number of days
    ' to today's date.
    MsgBox DateAdd("d", 7 - WeekDay(Date, vbSaturday), Date)