I'm not convinced that libofx is that much of a loss on an embedded device - especially when libofx and dependencies could add 5Mb to an existing installation - just for the shared libraries!
The screenshots of Grisbi in Maemo gave my the idea of adding grisbi and I've been trying it out on the desktop too. Once I'd tweaked the column widths for the transaction window (hidden away in Preferences), it is quite usable - although I can't see any way of it handling invoices.
My own gpe-cash is not making much progress - the GnuCash objects are just too resistant to use outside GnuCash. It may be easier to create invoices from grisbi/homebank data via CSV and estron.
This is aimed at the more powerful end of Emdebian devices but each package is still 50% smaller in Emdebian than in Debian, closer to 80% smaller if you count the reduced dependencies. The main difference is the use of TDebs.
Christian Perrier and I are planning on working on TDebs during DebConf8 and Extremadura so that bugs and fixes to support TDebs can be implemented in Debian as soon as Lenny is released. Removing translations from the maintainer uploads and translation bugs from the package BTS should make it a lot easier to update translations without requiring an NMU of the entire package (which is complete overkill IMNSHO).
Together with DEB_BUILD_OPTIONS="nodocs" support, TDebs are the simplest way to reduce package sizes and installation sizes in Debian/Emdebian.
(I just wish #448615 could be fixed so that I could get on with preparing patches for packages that install docs without using debhelper.)
ledger might have interested me except that it isn't really suitable for embedded usage as a CLI. That and the fact that the new version will not be C++ anymore. CashUtil was never aimed at embedded stuff but it could have supported a GUI as an add-on. The same cannot be done with ledger.