I have noticed from time to time how there is a gentle, bubbling interest in the liturgies of the (German) Reformed Church, Evangelical Synod, and Evangelical and Reformed Church, which entered the United Church of Christ in 1957.
But there is almost nothing about the liturgies online. Admittedly, the E&R worship book, at the beginning of the E&R hymnal, is still in copyright and presumably the oldest liturgies are in German, which would have a lesser appeal in the United States.
But what about the ones in-between? Is there an interest getting these online? It has certainly made a difference for study of the much-smaller Universalists, if the kind emails thanking me for getting the 1894 prayerbook are any reliable measure.