I am not very familiar with this (especially the non US ones) but there seems to be a few websites around. I’m personally wondering if I can find a suitable visiting role in virtual heritage, digital humanities, architectural computing, game-based learning, digital aesthetics etc. So if you are interested in these relatively obscure roles yourself, I’ll add links to this blog post when and if I find them.
General portal http://www.scholar-guide.com/tag/visiting-fellowship
Sardinia at Visiting Professor Program Cagliari
American Academy in Rome http://www.aarome.org/apply-to-the-rome-prize.php
Postdocs in Bologna http://www.ias.unibo.it/ISA/Proposals/VisitingResearchers/default.htm
Bogliasco http://scholarization.blogspot.com/2009/11/italy-liguria-study-center-for-arts-and.html
SAS UK http://www.sas.ac.uk/fellowshipprogrammes.html
Flemish Academic Centre http://www.kvab.be/vlac.aspx
HASTAC External Faculty Fellowships 2010-11 | HASTAC
Ireland HII Visiting Fellows | Humanities Institute of Ireland (HII)
ANU Canberra Australia http://rsha.anu.edu.au/hrc_internal_fellowships
Melbourne http://www.unimelb.edu.au/community/miegunyah/
Rhizome http://rhizome.org/announce/jobs/
Illinois http://www.iprh.illinois.edu/guidelines/digitalhumanities/default.aspxhttp://www.syracusehumanities.org/center/initiatives/
Syracuse http://www.syracusehumanities.org/center/initiatives/
Film Studies http://academicjobs.wikia.com/wiki/Film_Studies_2010-2011
Digital Medievalists Maryland: http://digitalmedievalist.wordpress.com/tag/job-vacancy/
Smithsonian http://invention.smithsonian.org/resources/research_fellowships.aspx
Rice (2011 closed) http://hrc.rice.edu/EFFCall.aspx