SolidWorks now do term licensing from a minimum of 3 months contact your VAR for details.
As Ron Chappell stated, there is a term license available thru your VAR. There is a chart available (SW Website?) which shows the economic "breakover" point - I believe somewhere around 6 months - at which it is more economic to buy the normal annual license.
Hmmm I was thinking since the SW EULA say you cannot sell or transfer into another owner your license so then perhaps i could make money by leasing my license jejeje