We present Slice WIM, a method for overview+detail visualization of volume datasets that explores the potential of new interfaces made possible by a virtual reality (VR) environment made of two display surfaces: an interactive multi-touch table, and a stereoscopic display wall. Slice WIM displays a miniature version of the 3D dataset within a head-tracked stereoscopic view such that it appears to float directly above the multi-touch table. Multitouch gestures on the table are then used to navigate through the dataset and to set slices (cutting planes) through the data. Leveraging the unique table+wall hardware setup, horizontal slices through the data are projected (like a shadow) down onto the table surface, providing a useful 2D data overview to complement the 3D views as well as a data context for interpreting 2D multi-touch gestures made on the table. We demonstrate several strategies for interacting with 2D "shadow slices" on the table surface as a method for controlling the WIM and exploring volumetric datasets. Applications of the interface to explore two different volume datasets are presented, and design decisions and limitations are discussed along with feedback from both casual users and domain scientists.