The following packages may be of help - easybmat
(easy block matrices), easyeqn
(easy equations),
easymat
(easy matrices),
easytable
(easy tables),
easyvector
(easy vectors),
delarray
(nested arrays),
theorem
(gives more choice in theorem layout),
subeqnarray (Renumbering of sub-arrays in math-mode),
subeqn (Different numbering sub-arrays).
