What is claimed is the ornamental design for a balloon weight, as shown and described.
FIG. 1 is a perspective view of a balloon weight, showing the new design;
FIG. 2 is an enlarged perspective view thereof.
FIG. 3 is a front elevational view thereof, the rear-elevational view being a mirror image thereof;
FIG. 4 is a left-side elevational view thereof, the right-side elevational view being a mirror image thereof;
FIG. 5 is a top plan view thereof; and,
FIG. 6 is a bottom plan view thereof.
The broken lines showing a balloon in FIG. 1 are included for the purpose of illustrating the invention in use, and form no part of the claimed design.