[prasanthmj]

I used this technique in my forms until I realised that the browser's auto-fill also works similar to the bot and will fill fields that has a familiar field name (email, name phone etc). Real users (many of them) who use browsers auto-fill feature will get blocked by this technique. If you add a field with a random field name bots ignore that field.

One thing that works still is using Javascript to create a hidden field and make that field mandatory. Run of the mill bots don't run Javascript yet. However this will exclude people who have disabled Javascript in their browsers.