Once seen as anomalies, high velocity clouds (HVCs) are starting to appear commonplace. Increasingly sensitive observations have found HVCs not only in and around our Galaxy, but also near other galaxies, between galaxies, and in the outskirts of the Local Group. In many cases, observations reveal signs of hydrodynamic interactions between the clouds and the gas around them. Such interactions have ramifications for both the clouds and the surrounding material. My group has been computationally modeling cloud-halo interactions. The simulated clouds erode on hundred million year timescales. They shed streamers of high-ion-rich gas that slowly decelerate and probably account for some of the low velocity high ions observed in the Milky Way's halo. They also entrain surrounding material, receiving a dose of metals in the process. On occasion, they produce X-rays. In this talk, Shelton will discuss the simulations as well as HVCs in general.