My Little Pony Nite Friends with Princess Twilight Sparkle. It functions as a bedside night light. It is available for $16.94 in Walmart Canada's webstore.
My Little Pony Grab 'n Glow. Grab 'n Glows are night lights that double as flashlights. This one features Twilight Sparkle and is available in Walmart Canada's webstore for $12.94. A purple Princess Twilight Sparkle version was also found.
They have been appearing in Walmarts in Canada. (via MLP Arena)
Last but not least are Charmlites! These small glowing charms can attach to backpacks and bags. Twilight Sparkle, Rainbow Dash, and Pinkie Pie versions are available. The links lead to listings for them on Walmart Canada's website but they do not seem to be available for purchase. They have also been found in K-mart stores in the US. (via MLP Arena)