According to the excellent source code evaluation tool, SLOCCount, our online soil survey (SoilWeb) code is worth about $268,543 and would require about 2 years of development time to re-create from scratch with a single developer working full-time. This is a fairly close estimate, as I have been working (part-time) on this code-base for 3 years now with most of the time spent in the first 2 years. For comparison, the current development version of GRASS 6 is based on about 230 person-years of development time and is worth about 31 million dollars. Neat!

 
SLOCCount Output

Total Physical Source Lines of Code (SLOC)                = 8,910
Development Effort Estimate, Person-Years (Person-Months) = 1.99 (23.86)
 (Basic COCOMO model, Person-Months = 2.4 * (KSLOC**1.05))
Schedule Estimate, Years (Months)                         = 0.70 (8.34)
 (Basic COCOMO model, Months = 2.5 * (person-months**0.38))
Estimated Average Number of Developers (Effort/Schedule)  = 2.86
Total Estimated Cost to Develop                           = $ 268,543
 (average salary = $56,286/year, overhead = 2.40).
SLOCCount, Copyright (C) 2001-2004 David A. Wheeler