From: http://xraysgi.ims.uconn.edu:8080/rpa-output/language/english/sentences/pangram.s

It is fairly straightforward, if time-consuming, to search for minimal
pangrams given a suitable lexicon, and the enclosed program does this. 
The run time is of the order of 20 MIPS-days if fed `Official Scrabble
Words', a document nominally listing all sufficiently short words
playable in tournament Scrabble in Britain.

I also enclose a lexicon which will reproduce the OSW results much more
quickly.

The results are dominated by onomatopoeic interjections (`pst', `sh',
etc.), and words borrowed from Welsh (`cwm', `crwth') and Arabic (`qat',
`suq').  Other lexicons will contain a very different leavening of such
words, and yield a very different set of pangrams.

Readers are invited to form sentences (or, less challenging, newspaper
headlines) from these pangrams.  Few are amenable to this sort of thing. 

    -- Steve Thomas