So half of us have very little money (3)
I believe the answer is:
sou
'very little money' is the definition.
(I've seen this before)
'so half of us' is the wordplay.
'half of' indicates taking half.
'us' cut in half is 'u'.
'so'+'u'='SOU'
'have' acts as a link.
(Other definitions for sou that I've seen before include "Little money once" , "Former small French coin" , "Very little to spend" , "Something of little worth" , "16 French coin" .)