From Wikipedia: Ability Office is an office suite for Microsoft Windows published by Ability Plus Software. An alpha version of Ability Office for Linux has been developed but work has stalled on this version. Ability Office is a low-cost (but not for free like OpenOffice.org) alternative to Microsoft Office and WordPerfect Office. Version 4 of Ability Office offers Office 2003 look and an expanded number of applications. Ability Office is popular with OEM system builders in the United Kingdom - Ability are based in England.

I send mail with ask when can I expect for a support OpenDocument Formats in Ability Office and I got answer: ODF is something we will look at after the release of v5. It's a big task - we think around 6 months (in other words, 3rd Qtr 2007). If we can, we'll release it as an update to v5. If, after initial investigation, it looks like it will take longer to implement, we'll
have to reconsider (e.g. maybe for v6).