A swami writer is a small, covert writing device used in magic and mentalism to create the illusion of precognition or telepathy. Also known as a “nail writer,” “thumb writer,” or “boon writer,” the swami writer allows performers to secretly write information such as numbers, words, or drawings, during a mentalism performance. This enables the mentalist to seemingly predict outcomes, reveal thoughts, or produce “pre-written” predictions under impossible conditions.

Swami writers come in forms including pencil lead, grease, or ink tips. Swami writers are typically attached to the thumb or finger using adhesive, bands, or clips, allowing for discreet use during a mentalism performance. Modern variations of the swami writer include devices like the “Ghost Writer,” which enhance comfort and functionality or the “Lincoln Best Boon Writer” which is the most stable boon writer (but doesn’t compare to the stability of a band nail writer. Common applications of the swami writer include predicting lottery numbers, revealing amounts of money in a participant’s pocket, or duplicating a thought-of word. The swami writer remains one of the most versatile tools in a mentalist’s arsenal, requiring practice to master but offering limitless possibilities for creating powerful mentalism effects.