Yes and No. If the target is SharePoint, you would need another conversion from SQL to SharePoint lists. Although technically SharePoint is powered by SQL, its data structure format is in fact not relational at all.
There are tools to automatically convert from Notes to SharePoint, my employer has used them on a large scale.
That said, a low cost Notes 2 SQL solution could definitely be interesting. As Jerry suggested, why not try it? Start small and see if it takes of. Don't forget to market it though.