Baseball America has posted a cumulative list of top-100 propects from the past 15 years. The Giants who have appeared on these lists:

1990
Steve Hosey, of (#52)
Eric Gunderson, lhp (#85)

1991
Royce Clayton, ss, (#23)
Steve Decker, c (#52)
Johnny Ard, rhp (#77)
Steve Hosey, of (#83)
Kevin Rogers, lhp (#89)

1992
Royce Clayton, ss (#6)
Salomon Torres, rhp (#30)
Steve Hosey, of (#83)
Derek Reid, of (#95)

1993
Calvin Murray, of (#33)
Kevin Rogers, lhp (#50)
Joe Rosselli, lhp (#65)
Steve Hosey, of (#83)

1994
Salomon Torres, metaphor (#22)

1995
J.R. Phillips, 1b (#73)
Dante Powell, of (#90)

1996
Shawn Estes, lhp (#72)
Joe Fontenot, rhp  (#96)

1997
Joe Fontenot, rhp (#45)
Dante Powell, of, (#92)

1998
Jason Grilli, rhp (#54)

1999
Jason Grilli, rhp (#44)

2000
Kurt Ainsworth, rhp (#58)

2001
Jerome Williams, rhp (#19)
Kurt Ainsworth, rhp (#30)
Tony Torcato, 3b (#60)
Lance Niekro, 3b (#85)

2002
Jerome Williams, rhp (#19)
Boof Bonser, titular sensation (#29)
Kurt Ainsworth, rhp (#58)
Tony Torcato, of (#83)

2003
Jesse Foppert, rhp (#5)
Jerome Williams, rhp (#50)
Kurt Ainsworth, rhp (#64)
Todd Linden, of (#82)
Francisco Liriano, lhp (#83)

2004
Merkin Valdez, rhp (#40)
Matt Cain, rhp (#91)

2005
Matt Cain, rhp (#13)
Merkin Valdez, rhp (#58)
Fred Lewis, of (#78)
Steve Hosey, of (Lifetime Achievement Award)

Throwing this out there for now, and I'll comment later.  One last thing, though.

Players ranked below Neifi Perez (#33) in 1997:

Bobby Abreu
Eric Chavez
Shannon Stewart
Mark Kotsay
Carlos Beltran
Torii Hunter

Not to pick on Baseball America with the benefit of 20/20 hindsight -- that would be ridiculously unfair -- but you can't help but giggle.