Thanks to the work of Clara Brasseur at STScI, the PanSTARRS1 3pi Survey is available in TOAST format and can be viewed in WWT! Here’s an embed demo:
PS13pi covers 3/4 of the sky (3pi out of 4pi steradians) in five colors (ugriz) to depths of about 23 mag and arcsecond spatial resolution.
Due to the way that the TOAST tiles are downsampled, you need to zoom in a fair bit to see the full richness of the data, and there are a few discontinuities in the visual appearance. But it is one heck of a dataset!
The WTML specification is here.