It's a modern Hotwheels car (I used to collect diecast). Not worth much. You'd actually be surprised at the value of matchbox vs. Hotwheels, though. The old Hotwheels cars that had the red lines on the wheels can get some serious cash. For instance, a pink, rear-loading beach bomb bus from 1969 sold for around $100,000 and that particular specimen is currently for sale at $150,000. It's considered the holy grail of Hotwheels... but I don't know of any Matchbox car that can hold that much value. I remember a box of 1960-1970 Hotwheels cars that someone found unopened in the back of a gas station (24? cars) sell for upwards of $20,000.
Now... all that being said... modern Hotwheels and Matchbox cars aren't, in general, worth very much. If you find Matchbox cars, they can potentially be older than Hotwheels cars (think tootsie toy cars).