My Top 5 Tips For Creating a Winning Viral e-mail:

No. 1 - Humour works well: It's a fact that most successful viral e-mails contain humour.

No. 2 - If it's not humorous, make it either topical, shocking, clever, strange, surprising or inspirational. 'Just another' slightly interesting e-mail won't cut it anymore. Conversly, you know you're on to a winner when someone e-mails you with the line "I don't normally forward on e-mails, but I had to with this one".

No. 3 - Use subtlety when promoting: If it's instantly obvious that you're advertising then people may not pass the attachment on. The main focus has to be off you in order to get a high 'forward factor'. Better to have a smaller percentage of click through's with mass exposure rather than a higher percent on just a few.

No. 4 - Know when to attach and when to host: Hosting a viral file on your web site is the best option as people will link to your site from theirs which can massively increases search engine optimisation. The thing to look out for, however, is traffic coming to your site who increase your bandwidth payments, but don't want what you're offering. (PowerPoint is a format I use for attachments and Flash for viewing on-line.)

No. 5 - Keep an eye on the file size: With broadband becoming increasingly popular, file size doesn't matter so much now, but 'smaller is always better'. And although Flash files are generally low in size, you have to take into account that some organisations screen or block attachments over a certain size.