Public Shared Function GetRandomNumber( _
	ByVal iLowerBound As Integer, _
	ByVal iUpperBound As Integer, _
	Optional ByVal iSeedMultiplier As Integer = 1) As Integer
	
	Dim Random As New Random(Now.Millisecond * iSeedMultiplier)
	Return Random.Next(iLowerBound, iUpperBound + 1)
End Function

Example:

For i = 1 To 5
	strKey = i.ToString & "|" & GetRandomNumber(1, 10, i).ToString
Next