I just messed around with Inkscape for a little while today. I drew this skyline. I cut the windows out of the buildings with Path -> Difference. The sky and the sun have gradients on them and the smoke is made with the calligraphy tool, blurred.

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1. Tracing with a Wacom tablet
2. Draw a shamrock with Inkscape
3. Trying to find an identity
4. Inkscape examples
5. About Inkscape