The ornamental design for a computermouse, as shown and described.
FIG. 1 is an upper rear perspective view of a computer mouse showing my new design.
FIG. 2 is a top view of a computer mouse showing my new design.
FIG. 3 is a bottom view of a computer mouse showing my new design.
FIG. 4 is a front view of a computer mouse showing my new design.
FIG. 5 is a rear view of a computer mouse showing my new design.
FIG. 6 is a right view of a computer mouse showing my new design; and,
FIG. 7 is a left view of a computer mouse showing my new design.
Any shading and cross-hatching are not features of the design but are utilized to illustrate the surface contours of the computer mouse in the drawings.