Sarenna runs awareness courses for UK retailers in Art Clay Silver: a composite clay-like material, made of fine silver powder and a harmless organic binder. As it's fired, in a kiln, on a kitchen gas hob, on a camping gaz ring, or with a butane torch, the binder vapourises and the metal powder sinters, leaving real solid 999 silver.

Rather than travel with materials and equipment and do live demonstrations, she uses video to explain the products and demonstrate the techniques that are used to make silver jewellery: usually rings, necklaces, and pendants.

At the end of her introduction, she takes a SushiDisk out of her handbag and sets it on the table. Then, after a few hypnotic seconds, she puts it in the USB port of her notebook computer and runs the movies. It's a totally memorable magic moment.

The SushiDisk looks realistic, life-size, hand-finished, and good enough to eat. The 1GB flash memory module is powered by the computer's USB port, so doesn't need a battery or a mains adapter.

She plugs it in, it flashes gently to show it's ready, the computer recognises it, adds it to its list of drives, and gives it a temporary drive letter, for example E.

Using My Computer or Windows Explorer, Sarenna finds and starts the presentation. When it's finished, she unplugs her SushiDisk. All done.

After the presentation, she gives her clients a few SushiDisks with product information and promotional videos. Ideal, as the Sushi Disk is problem free and requires no special computer skills.

Sarenna gave one to her boyfriend, Matt, as a Valentine's gift. It's usually plugged into his workstation and used as a portable backup and archive device: one he can take home, unlike the network server.