  We comment on various aspects of topological gauge theories possessing
N_{T}\geq 2 topological symmetry: (1) We show that the construction of
Vafa-Witten and Dijkgraaf-Moore of `balanced' topological field theories is
equivalent to an earlier construction in terms of N_{T}=2 superfields inspired
by Susy QM. (2) We explain the relation between topological field theories
calculating signed and unsigned sums of Euler numbers of moduli spaces. (3) We
show that the topological twist of N=4 d=4 Yang-Mills theory recently
constructed by Marcus is formally a deformation of four-dimensional super-BF
theory. (4) We construct a novel N_{T}=2 topological twist of N=4 d=3
Yang-Mills theory, a `mirror' of the Casson invariant model, with some unusual
features. (5) We give a complete classification of the topological twists of
N=8 d=3 Yang-Mills theory and show that they are realised as world-volume
theories of Dirichlet two-brane instantons wrapping supersymmetric three-cycles
of Calabi-Yau three-folds and G_{2}-holonomy Joyce manifolds. (6) We describe
the topological gauge theories associated to D-string instantons on holomorphic
curves in K3s and Calabi-Yau 3-folds.
