X-link to the Kobo thread for an sfnal Kobo Canada sale (some prices may be matched elsewhere or available in the US, especially from the larger publishers):
Until May 8th for $3.99 CAD or less, “Explore titles that are out of this world” with sf, fantasy, and horror titles, out of which a good chunk are both indie and romantic, but have some solid sfnal frontlist from Ursula K. Le Guin, Ken Liu, and Stephen Baxter, anthologies edited by Jonathan Maberry (Stoker Award-winner), translated works by Johanna Sinisalo (Tiptree Award), and backlist works from authors including John Zakour (previously DAW).
ETA: turns out there's also a corresponding Kobo US sale for the same prices in USD and a slightly different featured selection, until May 6th.