RCAdvisor's model aeroplane calculator tells you what it thinks is wrong, why that might be a problem, and what you might want to do to fix it. Runs on Windows, Mac or Linux
Nautical
(Third-party Links)
The RBBI Boat Propeller Calculator calculates Engine RPM; Gear Ratio; Propeller Pitch; Propeller Slip Speed or MPH
Use the Paper CD Case website to create a PDF file which can be printed and folded to create a paper CD case. For folding directions, see the about section. To add more tracks, a mailing address, or graphics to the case, use the advanced form. Mix CD cases created with the advanced form can be optionally added to a public mix CD database. To create a case for an existing CD, use the CD search engine to find the CD and it will fill in this form for you. Jewel case inserts can also be created.
If you're looking for a colour scheme to compliment one of your photos, all you need to do is upload your photo to Scrap by Color and the tool will spit out a grid of colors that compliment your picture.