This table uses both rowspan & colspan. It cannot be made with nested tables.

Let's walk through it. I've numbered the cells to make it easier to follow along.

Open your table.
Open a row.
Starting at the top left, the first cell we see is "Left". It spans 2 rows, so we'll will use rowspan=2.
Open a cell, enter your data, close the cell.
The next cell we see is "Top". It spans 2 columns, use colspan=2.
Open a cell, enter your data, close the cell.
There are no more cells in that row, so close your row.

Open a new row.
The next new cell is #3 - "Middle".
Open a cell, enter your data, close the cell.
Now we get to the "Right" cell.
It spans 2 rows. Use rowspan="2.
Open a cell, enter your data, close the cell.
Close your row.

Open the last row.
The only cell left is "Bottom". It spans 2 columns, so...
that's right, use colspan=2.
Open a cell, enter your data, close the cell.
We're done already.
Close the row & the table.

Here's the code:
<table align="center" border=3 cellspacing=0 cellpadding=0>
<tr>
<td align="center" width="80" rowspan=2 bgcolor="#000000" gradcolor="#cc0000">
1 Left
<td height="80" align="center" colspan=2 bgcolor="#000000" gradcolor="#00cc00" gradangle="90">
2 Top</td>
</tr>
<tr>
<td height="160" width="160" align="center" bgcolor="#000000" gradcolor="#666666" gradangle="45">
3 Middle
</td>
<td width="80" align="center" rowspan=2 bgcolor="#000000" gradcolor="#ffff00" gradangle="180">
4 Right
</td></tr>
<tr>
<td align="center" height="80" colspan=2 bgcolor="#000000" gradcolor="#0000cc" gradangle="90">
5 Bottom</td>
</tr></table>

Happy Tabling!
Gnubee