We have done something similar as Andrew suggested for a number of our sites that have many departments, and simply used an optional field, so that the department name shows on the grids. I know it sounds a bit of work, it works quite well. Export out and import back to populate the description of the account in the optional field. We found the description2 option confusing when trying to separate between the transaction description2 vs the account number description2, although the account description2 would work.

The only enhancement that would be further helpful would be the additional ability to show the department name in the grid of drill down to the View GL Entry, in the transaction view screen in GL. If you have a number of Department, the name details can help when viewing transaction entries.

Best,
Brian