there aren't a whole lot of tables in the e-texts -- we're talking literature, not spreadsheets -- but your system should handle tables anyway; not really big and hairy ones, just simple ones.
| table 1 | column 1 | column 2 |
| plain-text | yes | yes |
| x.m.l. | no | yes |
| html | yes | no |
| .rtf | no | yes |
| no | no |