Can one use Perrier water for Shaloch Manos with one other item?
This is an interesting question.
Based on the Gemara (7b), all authorities agree that one can give drink for mishloach manos (Terumas Hadeshen 111; Ran, Megillah 3b; Peri Chadash 695:4; Magen Avraham 11, and others).
It is possible that water was not generally considered a “drink” in the sense of being part of a meal, and was therefore considered unsuitable for mishloach manos. Moreover, water was possible not worth anything in the past (especially where it was widely available), and had no importance (see Nimukei Yosef Megilah 7) to render it suitable as mishnoach manos.
However, today mineral water is certain “part of a meal,” and it is worth money and carries a degree of “importance.” It therefore seems that one can given water for mishloach manos (see Divrei Malkiel 1:67; see also Nezer Ha-Torah, Sivan 5767, p. 308, where this is left as a matter of doubt).