Well, I'm going to assume it is a delimited file. If it turns out to be otherwise, we can make the modifications as needed. You can do this with a macro, just set the filename and delimiter, and run! If you'd like we can have the filename chosen at runtime, I left it as hardcoded for now. Try the following:

Sub ImportBigDelimitedTextFile()
 Dim openFile As String, vFileNum As Integer, eLine As String
 Dim vLine, vCount As Long, vDelim As String
openFile = "C:\mac.txt" 'Filename to import
 vDelim = ","                 'Delimiter
vCount = 0
 Workbooks.Add (-4167)
 vFileNum = FreeFile()
 Open openFile For Input As #vFileNum
 Do While Not EOF(vFileNum)
  Line Input #vFileNum, eLine
  vCount = vCount + 1
  vLine = Split(eLine, ",", -1, 1)
  Range(Cells(vCount, 1), Cells(vCount, UBound(vLine) + 1)) = vLine
  If vCount = 65000 And Not EOF(vFileNum) Then
   Worksheets.Add After:=Sheets(Sheets.Count)
   vCount = 0
  End If
 Loop
 Close #vFileNum
End Sub
Matt