WineCalc

It can be used to:

Calculate the amount of sugar that needs to be added to archieve a particular target SG or alcohol content in the finished wine.
Calculate the SG or alcohol content that is abtained by adding a particular amount of sugar to the must.
Calculate acidity adjustments.
Calculate the proportions, in which to blend two wines.
Convert various measurements between the Metric, US and Imperial systems.

Operating systems:

Take a look at some of the screenshots (click to enlarge):

It would be nice if you'd let me know what you think of it, or about your winemaking experiences by means of:
mipeman@yahoo.com or

WineCalc v2.40 (478k zip)

Check back for new versions/updates!