Ok … even though I am not a programming guru, I think your developer can do this little trick.

What you need to do is identify the IP address of your competitors coming to your site and checking your last cache, pages, whois and other info. Once you got their IP address, you can now redirect them to adult sites, serve them crazy prices or simply launch loud sounds on their speakers…. (not my idea … just heard it somewhere)

Instead of doing crazy stuff, what I would do is simply play with their heads and their wallets. How about making changes on your site that would confuse them and their strategy? Write that your conversion rate is 0.5% and you’re proud of it.

Use your imagination.