Bill Buchan just wrote about exporting data to Excel using a CSV file. There is actually a cool and surprisingly easy way to generate documents that show up in Excel as real spreadsheets, with formatting, colors, etc.
Simply create a file containing a HTML table. It may even work with multiple tables. You can use tags like <B> and <I> for bold/italic, and use the color attribute to set text color and background color. Use the colspan attribute to split a cell over multiple columns.
Save the file in Lotusscript as a regular text file, but with the extension XML XLS. Excel, as well as OpenOffice.org, will read the HTML and present as a nice spreadsheet.