"Dynamic Albedo of Neutrons" and all these Farnsworth fusors I've checked specs of Russian "Dynamic Albedo of Neutrons" module on Mars MSL rover - it can do 10^8 neutron pulses at 10 pulses per second. It works on D-T reaction in tiny linear accelerator, and power consumption is quite low (14W).
If you check specs for all these fusors (Farnsworth, Polywell, e.t.c) - they are happy to have 10^6 neutrons (best ones barely scratch 2*10^8) per second while having huge power consumption and short construction lifetime (<1hour). Does that mean that fusors are just a waste of paper from the science prospective, and real scientists routinely make neutron sources based on nuclear fusion with much better parameters/efficiency?
Update:
Fusor: http://en.wikipedia.org/wiki/Fusor

DAN: http://mars.jpl.nasa.gov/msl/mission/instruments/radiationdetectors/dan/
More info on Russian: http://www.federalspace.ru/main.php?id=58 
 A: I would not say that fusors are a waste, but so far they have turned out to not be very efficient. There are several factors working against them, compared to linear accelerator-based devices. Basically what it boils down to is the neutron production cross section.
In a fusor, the ions are in a plasma, and the mean free path is huge. So the effective cross section is small (in other words, ions have a relatively small probability of hitting each other and fusing), and you are spending a lot of energy accelerating ions (and electrons) that fuse very rarely. Perhaps efficiency can be improved, but the results speak for themselves -- the best efficiency I could find was 10^4 neutrons/W [2]. Despite a lot of work over the years, we do not have a good qualitative understanding of what goes on inside a fusor. 
Linear neutron generators have a huge advantage because they use solid tritiated metal hydride targets [1]. The ratio of hydride atoms to metal atoms is typically ~2, which presents a very large effective cross section compared to a plasma. In addition, the generated beam(s) of deuterons can be optimized for the target geometry. Furthermore, we have a better understanding of what goes on: it amounts to a fixed-target setup, which has a long history in nuclear physics.
There is the side issue of D-D vs D-T. Since the fusor is fed by gases and typically purges to atmosphere, hobbyists (and most scientists) operating fusors are restricted to the use of deuterium due to safety concerns. For a given energy in the typical range, the microscopic cross section for D-D is lower by an order of magnitude or more. But when the efficiency deficit is 10^4, 10^5, there is still a big gap even if D-T was used in both cases.

[1] See chapter 7 of PhD thesis by J.M. Verbeke, UC Berkeley, 2000
[2] Miley group, UIUC, 2004
