We are designing web based app that consists of forms. These forms have two main parts: big datagrid (table) and a panel that shows details about record selected in a table. There is a largely used option to perform actions on these records, and some of these actions require another (related) form. These forms are currently opened in modal windows. The problem is obvious: the user can't access information from the original form. Moreover, these modal forms can open other modal forms and so on.
So the question is: Is there any reasonable alternative to modal windows? My idea is to put these forms into some sidebar so that users can easily scroll back to the original form.