You can copy the macro Table2Lounge into a code module in Excel. If you copy it into a module in your personal macro workbook Personal.xls(b), it will be available in all workbooks.
To use it, select the cells that you want to copy, then run the macro (Alt+F8 will display the Macros dialog in all versions of Excel).
The macro will ask whether you want to include row and column headers, and whether you want to preserve vertical alignment (if you answer No, all rows will have Top vertical alignment).
As a result, the tags to create the table in a post will be placed on the Windows clipboard, ready to be pasted into your post.
Example:
Here is a screenshot of some cells in Excel:
Running the macro with those cells selected and answering Yes to both prompts will place the following "code" on the clipboard:
[table=1][tr=middle][td=center][/td][td=center][b]A[/b][/td][td=center][b]B[/b][/td][td=center][b]C[/b][/td][/tr][tr=bottom][td=center][b]1[/b][/td][td=left]Mary
had[/td][td=left]a[/td][td=right]little[/td][/tr][tr=middle][td=center][b]2[/b][/td][td=right]lamb[/td][td=right]and
its[/td][td=center]fur[/td][/tr][/table]
When posted, this results in
A | B | C | |
1 | Mary had | a | little |
2 | lamb | and its | fur |
Warning: the macro will ignore merged cells. The table tags in the Lounge don't support merged cells.