depends on a lot of things...
if you think you have a local market then it might be feasible... shipping is what usually kills even the sweetest monitor or case deal...
sometimes that type of thing can be good for E-Bay...
you also have to be sure you can do it well and for less than the local computer shop...
like the Tuttle's theme bikes... you could also customize to order...
little kids that want hotwheels or barbie cases...
someones girlfriend wants a pink case to match her room... lol... whatever
find a good base case to work with and you could do it...
Its actually something Ive toyed with doing myself..
however so far its been on a limited scale...
you could use some of the cheaper models from Amamax to work with...
maybe pick up some good deals on plain jane PSU's and mod them as well...
Heres some links for some possible candidates...
http://store.yahoo.com/amamax/spivatxmidto.html
http://store.yahoo.com/amamax/blatatxmicaw2.html
http://store.yahoo.com/amamax/poxcbl72atxm.html
http://store.yahoo.com/amamax/csmina161blackmecca.html
http://store.yahoo.com/amamax/poxcsi73atxg1.html
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you can often find some AMAZING deals on high end PSU's at
NewEgg's refurbished section, get a few
sleeving kits cheap from
SVC and some
CCFL's and
LED fans, and your set.... the rest is modding fun..lol