Product by National Instruments company. 
Allows programming in a language called G.
Has extensive/well documented libraries that come in handy when you are solving all kinds of 'automation' problems.
    * Signal Processing
    * Image recognition
    * Maths
    * ...

Connects to many instruments/devices by the use of [VISA],[IVI],[GPIB],[TCP/IP] or [UDP],[ActiveX]... name it LabVIEW plays it.  

Programming in LV is (even more) fun (than programming Tcl ;-)) because you do not need to type your program (G), you just draw it. 

(The result is something that is sometimes called spagetti-code, in the real meaning of spagetti)

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The most fun part is that it can be glued together with Tcl by the use of [tcom] as mentioned in [http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&safe=off&threadm=6bb003fa.0202041032.39b7328e%40posting.google.com&rnum=1&prev=/groups%3Fhl%3Den%26lr%3D%26ie%3DUTF-8%26safe%3Doff%26selm%3D6bb003fa.0202041032.39b7328e%2540posting.google.com] .