Drawn by hand, colored on PhotoStudio. The background was scanned from an encyclopedia.
Disclaimer: I don't own Star Wars and Star Trek
NOTE: Just addressing an interesting coincidence. Many have noted how similar Picard and Data look to Aang and Zuko from Avatar: The Last Airbender. Now while people have had the good graces not to go and say "rip-off!", for which I thank you all, I must also point out the submission date of this pic.
According to DA, it's November 3, 2004. Avatar first aired February 21, 2005 in the US, several months more after that here in the Philippines. As you can see, this was actually drawn way before all that.
Yoda: Gnome, I am not, Robot you are.
Data: Technically, it is said 'I am not a Gnome, but you are a robot.' Although, there is another error in your assumption; I am not a robot. Technically I am an Android. A humanoid artificial life form.
Picard: He's right, you know.